Table of Contents 

• Introduction — Wherein the author introduces the topic. 
• Chapter 1 — Wherein the author explains the basic technical procedure. 
• Chapter 2 — Wherein the author details her own personal recommendations for upgrading items that are level 145 or lower. 
• Chapter 3 — Wherein the author waxes Philosophical in the Analytic manner (and explains some things that many people won’t understand until they read this chapter, unless they have training in Logic and/or Probability and Statistics), because players really do need to know this in order to avoid making costly and/or embarrassing mistakes. 
• Chapter 4 — Wherein the author explains the meanings of several terms (this is more or less a glossary with extended notes, advice, and warnings), and gives links to other information on upgrading. 
• Appendix 1 — Wherein the author discusses Bloodseals, the Socket System, and Runes of Enchantment. 
• Appendix 2 — Wherein the author gives aid and assistance to those who have lost beloved gear through breakage while attempting to upgrade. 
• Afterword — Wherein the author warns the gentle reader not to rely on the older version of this Guide found on her website (because it’s older, and therefore, out of date). 
• Acknowledgements — Wherein the author thanks all those who have assisted in the preparation and updating of this Guide. 
• Addenda et Corrigenda — Wherein the author records edit notes for the curious-minded. 

Introduction 

There seems to be a lot of confusion over how to add pluses to armor and weapons, and what is necessary. Many players assume the need for Heaven Stones, which only increases demand, and therefore, price, for HSes. HSes are really unnecessary until the item is +12, but the items which are actually necessary may be costly in-game, or usually require the purchase of AP. Only weapons and armor pieces can be upgraded. 

There is currently no way for a player to add more than one plus at a time, no matter what method you use (with three exceptions only; see below under "PRS," "BBM," and "DRO" — however, a GM can, through a "Prime Stone" promotion [for which see below in Chapter 4], add more than one plus at a time). 

Chapter 1: How to Upgrade (The Basic Technical Procedure): 

To upgrade an item, you need to equip the item (double-click it in your inventory); obviously, if the item cannot be equipped due to level restrictions (this applies only to gear above a certain level, namely, 73 for weapons and 75 for armor, when the player must be the level of the item in order to equip it unless it has the "error" seal, which reduces the level requirement by 10; it does not apply to gear that merely decreases defense and such), then you cannot upgrade it. Then drag the appropriate type of smelt (normal smelt, LSS, CSS, HS, ES, PRS, PRO, or DRO; see below in chapter 4 for definitions of these acronyms and explanations of what they refer to, as well as my recommended method for using them in chapter 2) to the equipped item in the equipped items area of your inventory window (the upper part of the inventory window, which shows what gear you have equipped) and release. If the item is level 145 or lower and already +3 or higher, you will see a warning that the item may break without the use of "Insurance of smelting stone" (see below in chapter 4, under RoP I and RoP II). If you are using an LSS, CSS, ES, or PRS, there is no chance of breaking, so the message can be ignored. If you are using a normal smelt or an HS, you will want to use an RoP I (good on any item that is +3, +4, +5, +6, +7, +8, or +9) or you may want to use an RoP II (good on any item that is +10 or higher), in combination with the normal smelt or HS, in order to prevent breakage (an RoP will not prevent "no change," nor will it prevent downgrading; see further info below in chapter 4). 

For items that are level 146 or higher, there are only four options currently available for players. These are PRO, DRO, PRS, and Master Stones. A "Prime Stone" is something the GMs can do, but it’s a custom upgrade done by a GM (and it can be applied to gear of any level). See below in chapter 4 for more information on these items. 

Chapter 2: Giovanna’s Recommended Upgrade Method (for level 145 and below gear): 

For any item (any item that is up to level 145, inclusive) that is +0, +1, or +2, use a normal smelting stone that is the same level as, or a higher level than, the item you want to upgrade. If other items of that level or higher are difficult to find or costly (so that getting a normal smelt is difficult or costly), then you should use an LSS. You can use an HS or CSS, but I would not advise it, since CSSes are costly (and since HSes have the additional risks of breaking or downgrading the item; even when an HS is used with an RoP I, which won’t be an option at this point, the item can be downgraded – although unless the item was previously already +3 or higher and has since been downgraded, an HS should not downgrade or break any item that is not at least +3; there are reports, however, of HSes causing downgrades to items from +2 to +1 when the items were never +3 previously, but these reports have not been confirmed) and should be reserved for an item that is at least +6 already. Also, you also have the option of getting a Prime Stone and having the item upgraded to +16 by the GMs (see under "Prime Stone" in chapter 4 below). 

For any item (any item that is up to level 145, inclusive) that is +3, +4, or +5, use an LSS (guaranteed to add one plus with no chance of breakage and no chance of downgrade). You can use a CSS, but I would not advise it, since CSSes are more costly than LSSes, and should be reserved for items that are at least +6 already. You can use an HS, but I would not recommend it, since the HS can break or downgrade the item. If you must use an HS on such an item, make sure to use an RoP I with the HS, which will insure against the item being broken (but will not insure against the item being downgraded.). You can also use normal smelts with RoP I, which will insure against the item being broken. A normal smelt will not downgrade an item that is +9 or lower (but can break such an item, unless an RoP I is used too). Also, you also have the option of getting a Prime Stone and having the item upgraded to +16 by the GMs (see under "Prime Stone" in chapter 4 below). 

For any item (any item that is up to level 145, inclusive) that is +6, +7, +8, or +9, use a CSS (guaranteed to add one plus with no chance of breakage and no chance of downgrade, but usually requires purchase by means AP or has a very high in-game gold cost) or a normal smelt with RoP I (insures against breakage; a normal smelt will not downgrade an item that is +9 or lower). You can use an HS, but again, make sure you use it with an RoP I, to insure against breakage; be aware that the item can be downgraded in this manner. Also, although at this point it would be viewed as wasteful by some, you also have the option of getting a Prime Stone and having the item upgraded to +16 by the GMs (see under "Prime Stone" in chapter 4 below). 

For any item (any item that is up to level 145, inclusive) that is +10 or +11, use a CSS (guaranteed to add one plus with no chance of breakage and no chance of downgrade). you can use an HS, but make sure you use it with an RoP II, to insure against breakage; be aware that the item can be downgraded in this manner. You can attempt to upgrade it with an HS and no RoP II during an Upgrade Probability Increase Event (for which see below). Also, although at this point it would be viewed as wasteful by many, you also have the option of getting a Prime Stone and having the item upgraded to +16 by the GMs (see under "Prime Stone" in chapter 4 below). 

For any item (any item that is up to level 145, inclusive) that is +12, you have a choice, depending on how high you want to plus the item (most items below level 70 or so do not actually need to be higher than +13 for PvE purposes), and whether or not an ES has previously been used on it. You can either use an ES (guaranteed upgrade of +1, with no chance of breakage or downgrade) on it to make it +13 and then stop trying to upgrade the item, or you can use an ES on it to make it a +13 and then use 4 Master Stones +17 to get it to +17, or you can use an HS with an RoP II to attempt to get it to +13 (this method, however, although it will prevent breakage of the item, may still result in a downgrade back to +10). If you intend to try to get the item to +15 or +16 by means of HSes, it is recommended that you use an HS with an RoP II to attempt to get the item from +12 to +13 (or that you make your attempt with an HS and no RoP II during an Upgrade Probability Increase Event, for which see below), because an ES can only be used once on any item. Once an item is +16, the only way to add any further plus is through Master Stones (as discussed in chapter 4 below). See below in chapter 4 under PRS and BBM for additional options once the item is +13. Also, although at this point it would be viewed as wasteful by most, you also have the option of getting a Prime Stone and having the item upgraded to +16 by the GMs (see under "Prime Stone" in chapter 4 below). 

For any item (any item that is up to level 145, inclusive) that is +13, you have a choice, depending whether or not an ES has previously been used on it. You can either use an ES (guaranteed upgrade of +1, with no chance of breakage or downgrade) on it to make it +14 (but only if no ES has ever been used on the item previously), or you can use an HS with an RoP II to attempt to get it to +14 (this method, however, although it will prevent breakage of the item, may still result in a downgrade back to +10, and will make any attempt to use an ES afterward pointless), or you can use an HS without an RoP II during an Upgrade Probability Increase Event (for which see below). It is recommended that you use an ES to get an item from +13 to +14. If you later downgrade the item, you will never be able to use an ES on that item again. See below under PRS and BBM for additional options. Alternatively, once the item is +13 via an ES, you can upgrade it further with Master Stones (see below in chapter 4). Also, although at this point it would be viewed as wasteful by most, you also have the option of getting a Prime Stone and having the item upgraded to +16 by the GMs (see under "Prime Stone" in chapter 4 below). 

For any item (any item that is up to level 145, inclusive) that is +14 or +15, you have three options: you can use an HS with an RoP II on a +14 item to attempt to get it to +15 (this method, however, although it will prevent breakage of the item, may still result in a downgrade back to +10, and if that should happen and an ES has already been used, you cannot use another ES on the item later), and you can do likewise with an item that is +15 in order to get it to +16. It is possible to do this with an ordinary smelt instead of an HS, but the odds of success are lower. An ES will not make a +14 item into a +15 item. An ES will not make a +15 item into a +16 item. In the event of an Upgrade Probability Increase Event (see below), you may opt to risk using an HS without an RoP II. Contrary to myths, superstitions, and rumors, it is possible to break an item while trying to go to +15 from +14 (and while trying to go from +15 to +16). You may instead use a Master Stone for each plus at this point. Also, although at this point it would be viewed as wasteful by most, you also have the option of getting a Prime Stone and having the item upgraded to +16 by the GMs (see under "Prime Stone" in chapter 4 below). See below under PRS and BBM in chapter 4 for additional options. 

For any item that is level 146 or higher, you have only 4 options, PRO, DRO, PRS, and Master Stones (see chapter 4 below for information on all of these), although the GMs can, through a Prime Stone, upgrade the item to +16 in one fell swoop. 

Chapter 3: A Few Words about "Upgrade Probability Increase Events," Probability, Statistics, and the Dreaded "Gambler’s Fallacy": 

Occasionally, the GMs will hold an Upgrade Probability Increase Event (commonly called "an Upgrade Event"). There is much confusion over the meaning of the percentages in such an event. The highest increase of probability is 200%. This is not a 200% chance of an upgrade. What "200%" during such an event means is that the normal chance has been doubled. Until very recently, we did not know the exact normal probability for an HS to upgrade an item, but we knew that it is higher than that of a normal smelt. Here’s where it gets tricky, because we do have more info now, and the exact probabilities are not entirely static; two option probabilities are static and two option probabilities are affected by what plus the item already has. 

The Devs have finally provided the exact percentages, on a base chance which changes depending on what plus the item already has: 

For a normal smelt, regardless of the item level (but see under PRO and DRO below): 
Chance to Upgrade = 50% (minus an increasing amount for each plus past 0) 
Chance to Break = 50% (plus an increasing amount for each plus past 0) 

For an HS, regardless of the item level (but see below under PRO and DRO): 
Chance to Upgrade = 60% (minus an increasing amount for each plus past 0) 
Chance of no change = 20% (plus an increasing amount for each plus past 0) 
Chance to break = fixed at 7% 
Chance to degrade (downgrade) = fixed at 13% 

The higher the plus on the item, the less chance of successful upgrading. Yes, you can break a +14 item trying to go to +15 using an HS alone or a normal smelt alone (and the chance to break it using a normal smelt alone is actually greater than the chance to break it using an HS alone, as stated above), and you can break a +15 item while trying to go to +16 using an HS alone or a normal smelt alone (ditto). See: Busting myths 1 heaven stone at a time . 

The exact formula for the changes to probability based on what plus the item already is has not been revealed. If you ask, we’ll simply answer that we can’t tell you, because we don’t have that information. That lack of information is due to the choice of the Devs. 

A 200% Upgrade Probability Increase cannot be a 100% Upgrade Probability, except when dealing with items that have a very low plus, and in those cases, the probability is 100%, during a 200% Probability Increase Event (but it would already be 100% or very close to it on those very-low-plussed items even without such an event). 

In addition, many people do not understand the difference between Probability and Statistics, and do not have a firm grasp of Probability itself; this is not an insult, as people must be trained in Logic and/or specifically in Probability and Statistics in order to understand properly, and far too few people get such training (Logic should be a required course in both high school and university, for a number of reasons, but that’s a dissertation for another time and place). 

Probability reflects a chance; Statistics reflect a tested rate. 

Probability and Statistics are not necessarily identical, due to the nature of Probability. Each attempt has the exact same Probability as any other attempt. The Probability does not increase or decrease with the number of attempts, nor with the number of failed attempts, nor with the number of successful attempts. Each attempt is statistically independent of every other attempt. There is no "cumulative probability," except where it is known to exist (that is, in the cases of those two probabilities which are not fixed, but affected by what plus the item already has). In other words, the chance to break, and the chance to degrade, are ALWAYS the same percentage, no matter what the plus of the item, and no matter how many HSes you have used on the item. 

It is possible to toss a coin 99 times and get tails each time, even though the Probability of getting heads was 50% on each toss. The 100th toss has neither a greater nor a lesser chance of coming up heads; it is still a 50% probability of getting heads, and a 50% probability of getting tails. 

To assume otherwise is to commit "the Gambler’s Fallacy" (also known as "the Monte Carlo Fallacy" and "the Doctrine of the Maturity of Chances," which some have lately tried to conflate with "cumulative probability," not understanding that, under ordinary circumstances, when something is not set up to alter probability based on past successes and/or failures, there is no such thing as "cumulative probability"). See The Gambler’s Fallacy for a complete explanation. 

This applies to static Probability only. In cases where other factors have an influence on the Probability, there is obviously some increase or decrease of the Probability, such as has been stated above in the formulae for normal smelts and HSes, but onlyin the cases stated to be affected (so, for example, the chance of a degrade and the chance of breakage on an HS are static and unaffected by previous successes or failures, and there is not, nor can there be, any "cumulative probability" of either of those results). 

Understand: "fallacy" means "incorrect inference form" (or "faulty reasoning"); this is not an insult or slur against those who commit fallacies, as even those trained in Logic occasionally do so. However, those who are not trained in Logic (which is the vast majority of people, alas) will typically do so rather often. Logic is a discipline, and in order to master it, one must undergo study, training, and practice. Logic is in this respect no different from any other discipline. 

There is a lot of demand for Upgrade Probability Increase Events, because an HS by itself will never downgrade to +10 from any other plus except +11, whereas with an RoP II, anecdotal evidence based on poorly and/or improperly collected Statistical data insists that there will almost always be a decrease to +10 from +14 before you hit +15 (and you may choose to believe this if you like, but it ignores the Laws of Logic, which are Absolute, Logic and Mathematics being the only Pure Sciences), and since these events increase the probability of a successful upgrade, many people do not use RoP II in their upgrade attempts during such an event. However, these events, when known in advance, result in server latency (lag, disconnections, "Timed Out" messages when attempting to sign in, "Account already in use" messages when attempting to sign in, etc). They also tend to drive the price of HSes higher. Fortunately (in my opinion), these events are now random, which should reduce server latency during such events, and which should (were it not for human greed) also slow down (and possibly even stop or reverse to some extent) the increase of HS prices (which affects other prices as well). 

Chapter 4: Explanations of Terms: 

Ordinarily, terms should be defined up front. However, since the main points I hope to get across in this guide might never be read if these terms were defined at the beginning of the guide, I have instead chosen to place them at the end, as a sort of glossary. 

Smelt 
Smelting Stone – 

• A normal Smelting Stone can be made by going to the Transmuter NPC (in the town of Randol or in Dratan City), out of any weapon or armor piece that is not already plused. There is an in-game gold fee for transmuting the item into a smelt. 
• These can also be purchased from other players or from the Merchant Mart using in-game gold. 
• You need a smelting stone that is the same level as (or a higher level than) the item you want to plus. 
• It will add no more than +1 to any weapon or piece of armor. 
• It may fail to add a plus; that’s a risk, but relatively light. 
• If the item is already +3, it may fail to add a plus (no change), it may add a plus, or it may break the item. 
• If you use it in combination with an RoP I (useful only if the item is +9 or lower), the item will not break, but the smelt may still fail to upgrade the item (no change), or it may upgrade the item (again, by one plus only); it will not downgrade the item if used with an RoP I. 
• If you use it in combination with an RoP II (useful only if the item is +10 or higher), it will prevent the item from breaking, but the item may upgrade, may downgrade, or may have no change. 
• You may use more than one normal smelt on an item. 
• Will not work on any gear that is level 146 or above. 

LSS 
Lucky Smelting Stone – 

• A Lucky Smelting Stone can be purchased from the Item Mall with AP, or bought from other players or the Merchant Mart. 
• In very rare cases, it may also be a prize in a GS-run or GM-run event. 
• It guarantees an upgrade of +1 to any item that is +0 to +5. 
• Once an item is +6, there is no use for an LSS on the item. 
• There is no need to use RoP I with an LSS. 
• An LSS will not give a +6 upgrade; each LSS will give a +1 upgrade only, up to +6. 
• You may use more than one LSS on an item. 
• Will not work on any gear that is level 146 or above. 

CSS 
Chaos Smelting Stone – 

• A Chaos Smelting Stone can be purchased from the Item Mall with AP, or bought from other players or the Merchant Mart, or (occasionally) may be gotten by unsealing a Chaos Ball at Estella (in the town of Randol or in Dratan City). 
• In extremely rare cases, it may also be a prize in a GS-run or GM-run event. 
• It guarantees an upgrade of +1 to any item that is +0 to +11. 
• Once an item is +12, there is no use for a CSS on the item. 
• There is no need to use RoP I or RoP II with a CSS. 
• Each CSS will give an upgrade of +1 only, up to +12. 
• You may use more than one CSS on an item. 
• Will not work on any gear that is level 146 or above. 

HS 
Heaven Stone – 

• A Heaven Stone can be found in drops from killing mobs, can be purchased from the IM with AP, or bought from other players or the Merchant Mart. 
• It can also be gotten from a successful completion of the Sunday Quiz event, or gotten by playing the Moon Statue or by unsealing a Chaos Ball at Estella. 
• In rare cases, it may also be a prize in a GS-run or GM-run event. 
• An HS is essentially a normal smelt with a higher chance of success. 
• An HS should not break or downgrade any item that is below +2 (but see above about the possibility if the item was previously +3 or higher and has since been downgraded). 
• If an HS is used on an item that is +3 or higher, it can upgrade the item by +1, it can break the item, it can give no change, or it can downgrade the item. 
• If used with an RoP I on an item that is +9 or lower, the item will not break, but the item may upgrade by +1, may downgrade (by -1), or may have no change. 
• If used on an item that is +10 or higher, the HS may upgrade the item by +1, may break the item, may give no change, or may downgrade (by -1). 
• If an HS is used with an RoP II on an item that is +10 or higher, the item will not break, but it may upgrade (by +1), may have no change, or may downgrade (back to +10; that is, this could be a downgrade of more than -1). 
• Each HS will, if successful, give an upgrade of +1 only. 
• You may use more than one HS on an item. 
• Will not work on any gear that is level 146 or above. 

ES 
Extreme Stone – 

• An ES can be purchased from the IM with AP, can be purchased from another player or the Merchant Mart with in-game gold, or can be purchased with Reputation Points from Magical Shopkeeper Coen in the town of Randol. 
• Do not expect this to be a prize from any event; the possibility is not non-existant, but it is highly unlikely. 
• An ES guarantees an upgrade of +1 to any item that is +13 or lower. 
• It is unwise to use an ES on any item that is not at least +12 already. 
• It will not make a +14 into a +15, nor will it make a +15 into a +16. 
• There is no need to use any RoP with an ES. 
• If you want to make the item into +15 or +16, you should use the ES when the item is +13. 
• If you are willing to settle for a +13 item, use the ES when the item is +12 (but be aware that such an item will not be worth as much gold as a +13 which has not had an ES used on it if you elect to sell the item). You may then use Platinum Refining Stones (available from the IM or from other players or the Merchant Mart), which will add a +1, +2, or +3, but only for 24 real-time hours, or use Bonus Books of Melding (available from the IM, or from other players or the Merchant Mart; note that once opened, a Bonus Book of Melding cannot be bought/sold by players or put into or bought from the Merchant Mart) and a C1 weapon cover or C1 armor cover (covers are ordinarily only available from the IM, but there are some events which grant them) to get the item a plus that lasts for 30 real-time days. Note that C1 Covers are currently unavailable, and so BBMs are not functional. 
  
• If you are willing to pay the higher cost, you may use the ES when the item is +12 and then use Master Stones instead of HSes to add further plusses. 
  
• [b]An ES can only be used once on any item; if an item was ever plussed with an ES, and later downgraded to +10, an ES can never be used on that item again. 
• Will not work on any gear that is level 146 or above. 

RoP I or RoP 1 
Rune of Protection I – 

• Referred to in-game during upgrade attempts as "Insurance of smelting stone," an RoP I can be purchased from the Item Mall with AP, from other players with in-game gold, or from the Merchant Mart with in-game gold. 
• It insures against the breaking of an item that is +3 to +9, when used with a normal smelt, an HS, a PRO, or a DRO. 
• It does not guarantee an upgrade. 
• It does not prevent downgrading when used with an HS. 
• You can use more than one RoP I on an item (but only one per upgrade attempt). 
• May be used on gear of any level. 

RoP II or RoP 2 
Rune of Protection II – 

• Referred to in-game during upgrade attempts as "Insurance of smelting stone," an RoP II can be purchased from the Item Mall with AP, from other players with in-game gold, or from the Merchant Mart with in-game gold. 
• It insures against the breaking of an item that is +10 to +15, when used with a normal smelt, an HS, a PRO, or a DRO. 
• It does not guarantee an upgrade. 
• It does not prevent downgrading when used with an HS or a normal smelt (and in fact will make any downgrade from an HS on an item that is +11 or higher result in a +10 item). 
• You can use more than one RoP II on an item (but only one per upgrade attempt). 
• May be used on gear of any level. 

PRS 
Platinum Refining Stone – 

• Available from the IM or from other players or the Merchant Mart, a PRS guarantees a +1, +2, or +3 upgrade to any item, but that upgrade will last only 24 real-time hours. 
• It is possible to get an item to +17 with a PRS (and it will show as +17). 
• Only one PRS can be used on an item at a time. 
• Can be used on gear of any level. 

BBM 
Bonus Book of Melding – 

• Available from the IM or from other players or the Merchant Mart (but once opened, a BBM cannot be bought or sold by a player, nor put into the Merchant Mart), a BBM is used with a piece of armor and a piece of an armor cover (C1 Covers only), or with a weapon and a weapon cover (again, C1 Covers only; covers are ordinarily available only in the IM, but School covers for armor, and "Strange Weapon Covers," can be gotten through the Wendy Bear event; they cannot be bought or sold by players or through the Merchant Mart, whether bought from the IM or obtained from the Wendy Bear event). 
• In order to use a BBM, it must first be opened to show what the bonus is (you can get a bonus of +1, +2, or +3). 
• It is possible to get an item to +17 with a BBM (although what will be displayed will be [+14][+3], [+15][+2], or [+16][+1], and not +16). You may see an indication of a higher plus (such as [+16][+2], for example) on an item, but it will only have the effect of a +17 item. Players often dispute these claims; this has been tested several times, however, and unless something has changed, these claims are still accurate, regardless of appearances. 
• Only one BBM can be used on any given item at a time. 
• Will not work on any gear that is level 146 or above. 
• Note that C1 Covers are currently unavailable (with very rare exceptions, and so BBMs cannot be used (with very rare exceptions, namely, Shades/Sunglasses and Phoenix gear). If a player receives a BBM from an Upgrade Box while the C1 Covers are unavailable, he/she may submit a Contact form and gift the BBM to a GM in exchange for a new Upgrade Box (confirmed by GM Yatou); be advised, the GMs can determine where the BBM came from, and they will check (note also that you are free to save your BBMs for some future time in which C1 Covers may again be available, instead of getting them replaced with Upgrade Boxes, but be aware that there is no estimate on how long it may be before C1 Covers will be available again). 

PRO 
Purified Refining Ore – 

• Will not work on any gear that is level 145 or below. 
• These can be got from drops by killing mobs, by exchanging Affinity Points with Sio Committee Manager Watson (after you have bought his "friendship"), bought from other players, bought through the Merchant Mart, or bought from the IM. 
• These have a 100% probability of successful upgrade (by one plus at a time) up to +5. 
• Success rate increases and destruction rate decreases for gear below level 156. 
• These have four possible outcomes: successful upgrade, breakage, no change, or degradation (downgrade). 
• Each PRO will (if successful) give an upgrade of +1 only. 
• It is possible to use more than one PRO on an item. 
• RoP I and RoP II can be used with these. 

DRO 
Devil Refining Ore – 

• Will not work on any gear that is level 145 or below. 
• These can be gotten from Sio Committee Manager Watson (after you have bought his "friendship" and after you earn sufficient Affinity Points), bought from other players, bought through the Merchant Mart, or bought from the IM. 
• These have a 100% probability of successful upgrade (by one plus, two pluses, or three pluses at a time) up to +5. 
• Success rate increases and destruction rate decreases for gear below level 156. 
• These have two possible outcomes: successful upgrade (by +1, +2, or +3), or breakage. 
• Each DRO will, if successful, give an upgrade of +1, +2, or +3 only. 
• It is possible to use more than one DRO on an item. 
• RoP I and RoP II can be used with these. 

To be precise, PRO and DRO cannot be used on any armor lower than level 146 or any weapon lower than level 149. 

Master Stone 
Master Stone – 

• This is not an item. Update: This is now an item, but it still cannot be used by players in the ordinary manner for upgrading an item, only bought/sold/traded (the inventory icon looks like the LC logo, and will show the plus when you mouse over it). In order to obtain the upgrade from the item, the player must visit the Master Stone NPC in Randol, who goes by the name xLeGioNdeHoNORx. 
• This is the only permanent way to get an item to a plus above +16. 
• There are several varieties of Master Stone: Master Stone +17 (this will add a single plus to any item that is not already +17), Master Stone +19 (this will add a single plus to any item that is not already +19), Master Stone +21 (this will add a single plus to any item that is not already +21), Master Stone +23 (this will add a single plus to any item that is not already +23), Master Stone +25 (this will add a single plus to any item that is not already +25), and Master Stone +26 (this will add a single plus to any item that is not already +26), as well as Armor Stone (this will add a single plus to any armor piece). The upgrade is guaranteed (no chance of failure, breakage, or downgrade). 
• It is possible by means of this upgrade to get an item to +26 permanently. 

Prime Stone 
Prime Stone – 

• This is a custom upgrade done by a GM; a Prime Stone cannot be used by an ordinary player, not even through the Master Stone NPC. 
• A Prime Stone will upgrade any item of gear (armor or weapon), regardless of level and regardless of plus, to +16. 
• If you qualify for a Prime Stone upgrade, you will need to follow the instructions in this thread: How to Redeem a Prime Stone Ticket. 

For further information, see: 
Giovanna’s First Post about the Supposed Value of HSes 

For other guides on Upgrading, see: 
The Last Chaos Wiki on Smelts and Upgrading 

The Last Chaos Wiki on Runes of Protection 

Appendices 

Appendix 1: Seals 

Although adding seals to gear is not, technically, equivalent to the "upgrading" of gear, information on how to do so is also helpful when you seek to get the most out of your gear. Some gear (weapons that are level 73 or higher and armor that is level 75 or higher) comes with seals already determined, and that gear has fewer options for additional seals. All other gear ordinarily has two options for additional seals, "Bloodsealing" and "the Socket System." In the case of the 73+ weapons and 75+ armor, the only option ordinarily available is "the Socket System." As such, I’m presenting some discussion of these topics and links to additional information. 

Appendix 1a: Bloodsealing 

Bloodsealing is discussed here: 
Bloodsealing 
Bloodseal list 

I would like to add the information that Bloodseals can be added to gear before that gear has the "Bloodseal Ability" note, by means of an AP item known as a "Crystal of Blood and Sweat," discussed in this thread, which, however, does not explain that the speed at which one typically goes through low-level gear often does not allow sufficient time for all Bloodseals slots available to be earned. At low levels, Bloodseals can be very helpful. Therefore, if you have the AP and are willing to use it on a low-level character’s gear for the advantages provided by Bloodseals, buying a few Crystals of Blood and Sweat is not a bad idea to get the most out of your gear. 

Appendix 1b: The Socket System 

The Socket System in LC-USA is a means of adding additional seals beyond what would normally be available on gear. A rudimentary guide can be found here: The Socket System Guide (Official), and a growing unofficial guide (at the Wiki) can be found here: Socket System; there is also a visual guide here: [Guide] Socket System: The Ultimate Visual Guide. In addition, you may want to read about Socket Gem Upgrading in threads like: 
Socket Gem Upgrading Results, Socket Calculations, and How to Create 2% – 5% jewels …. 

For information on Level 5 Socket Gems, see: Presenting: THE LOOTFORGE!, a new Web Item Mall feature, which can be found here: The Loot Forge. 

If you won a promotion to have a socket added to your item, or to have a gem added, here’s what you need to know: 
Socket and Gem Unlocker Redemption. 

Appendix 1c: Rune of Enchantment 

Gear above a certain level (73 for weapons, 75 for armor) comes with seals already implemented (but can still have socket gems added). However, sometimes the item is missing a seal that the Modifier indicates should be on the item (for example, a pair of "Speed up Boots" has the Modifier "Speed up," and it should have a seal included that increases movement speed by 30%). In order to get this missing seal added to the item, you need a Rune of Enchantment. This is a service offered by the GMs, and to redeem the seal, you will need to follow the instructions in the Rune of Enchantment Redemption thread. 

Appendix 2: OMG!!!11!1!11!shiftone I broke my coveted +14 Disco Popsicle of Funky Groove with a stinking HS that JeauxPhreadBilderbubbaXoZzYrOcKs sold me!!! 

Let this despair pass from thy mind, weary mortal, for the Powers That Be have heard thy lamentations and, yea, even thy supplications. Behold: The Unbreak Hammer, a mighty and awesome tool stolen from the Forge of Ήφαιστος by the erudite GM Ozymandias (who hath now fled these precincts in order to avoid the wrath of the Smith of the Gods). 

Afterword 

An older version of this guide is mirrored on The Witch’s Brew, my LC website (also linked in my signature). I have no idea when I will have time to re-code the current version in order to place it on that site. Until such time is available, you would do well to ignore that site entirely (for it is sorely in need of major updating throughout its pages). 

Acknowledgements 

A thousand thanks to slickx for confirming some of my info during the preparation of this guide, and a hundred thousand thanks to misty128 for proofreading and giving additional assistance. Give them some karma, please (you may also give me some karma if this guide was helpful to you). 

Thanks also to b1ank for post-publication input (which has led to editing of the original post). 

Thanks as well to irene_tas, dinosue2, jaretlafoudre, and aeria_ks1lent, for assistance with the 146 and above gear. 

Thanks as well to GM_darasuum for information on the updated Master Stones as inventory items. 

And thanks to GM Yatou for updated information following the increase of the upgrade cap from +15 to +16. 

Additional thanks to GM ebilfish for updated information on Master Stones, Armor Stones, and Prime Stones. 

Credits go to Giovanna_X.