Socketed Equipment

ALL OF THEM.

"There exist five varieties of magic powder, each corresponding to one of five different elements; Fire, Water, Thunder, Earth, and Air. It is possible to augment items with these powders, if one is versed in the art of enchantment. [...] Certain items have a higher magical capacity, and thusly are able to hold more powders within them. Some have many, some have few, others still have none."

— Excerpt from Chapter 1 of the Powder Manual, Wynncraft

A piece of Socketed Equipment comes with a number of empty "sockets," into which can be placed various "gems" (ie. Power Crystals) to add more qualities to said piece of equipment: a ruby might add Fire damage or resistance to fire, a black diamond might add Life Drain, and so on.

In the original concept of the trope as presented by Diablo II, once a gem was in a socket, the match was permanent and that was the end of the story. When combined with Randomly Generated Loot (which Diablo also featured), this meant that every piece of EQ you encountered was completely unique, even before you socketed it out. It also meant you lived in fear of socketing a gem and then, on the very next dungeon crawl, uncovering an even better piece of gear you ought to have saved the gem for.

In technical terms, this trope is a modular customization scheme in which you can create gear with any combination of pre-determined qualities you desire. In general, it's only seen in games with Randomly Generated Loot, since this ups the possible combinations immensely; it also means you can't control an item's quantity of sockets, style (IE "Is this a weapon my character class can use?") or pre-existing enchantments, and instead have to spend a lot of time adventuring (or Save Scumming) in the hopes of finding that perfect piece of gear. Since the entire Diablo franchise (and every clone of it, for that matter) is built on this trope, it is clearly a very effective time sink.

Supertrope of Gun Accessories, which is basically this but with less abstract stat boosts. Contrast Item Crafting, which this is the aftermarket equivalent of.

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Video Game Examples:

• Absented Age: Squarebound: Upper body and lower body armor can hold up to five Ectoplasms, which increase the stats separately from leveling the equipment up. The only way to remove Ectoplasm is to use Ecto-Cleaner.
• The fishing gears in Ace Fishing has slots that can be loaded with pearls. The additional value of the pearls are randomised, though.
• Aion has sockets in all of the armors, weapons, and shields. The number of sockets usually depend on the item's rarity, but can vary in some exceptions. Players can slot manastones into these sockets to provide a direct boost to their stats, although putting more than one in an item may cause the socketing to fail, which destroys ALL the manastones already in that item! Some weapons also have a "godstone" slot that will accept one godstone that will give the weapon a chance to proc a specific effect, such as additional damage. And, on top of all of that, the players themselves can earn up to five stigma slots and three advanced stigma slots, which are used for slotting additional skills you can't obtain any other way.
• In ANNO: Mutationem, each weapon has three sockets for enhancement chips that would increase it's strength, amplify critical damage, or double penetrating attacks against armor health.
• Ar nosurge does away with equipment completely and instead the characters install parts called Plugins into their weapons and armor, which are predetermined. These include increasing Break for the enemies, causing them damage similar to poisoning, increasing the regen rate at the start of some turns, and such.
• Arc Rise Fantasia has an unusual version. Every single weapon in the game comes with a 4-by-4 grid, that houses two "Arm Forces" - gems, that come in several shapes. Each Arm Force provides a unique bonus, ranging from simple stat upgrade, to bonus damage to a certain enemy type, to automatic healing of debuffs. By using the weapon long enough, the player can unlock the grid, and remove one of these Arm Forces for use on any other weapon. The other gem is "native" and can't be removed. If the grid is filled completely, the weapon will unlock its Weapon Secret - a powerful Arm Force that doesn't take place on the grid, but can't be removed from the weapon. Infinity +1 Sword of every character lacks the Native gem, allowing for broader customisation.
• Capella's Promise has orbs, which can be placed into equipment for bonus effects but can never be removed.
• The way that you enhance your superpowers in City of Heroes works in a similar fashion. On level-ups that don't give new powers you will instead get 2-3 slots that you can distribute among your powers for a total of 6 slots per power. Enhancements go into those slots and work to improve the stats of that power such as increasing accuracy and damage or reducing recharge time. There are also special types of enhancements that improve 2, 3 or even 4 stats at the same time. You can also mix and match enhancement types. Just because you slotted 1 piece from the Touch of Death set doesn't mean that you must use only that set for that power (although you need more pieces of it to get the set-bonuses for having X number of that set's pieces). It's common place to mix different enhancement types and sets to get certain desired stat boosts, which is referred to as "frankenslotting".
• Present in the original Dark Cloud, each weapon has two to five slots for attachments. When a weapon is upgraded, it absorbs those attachments, adding them to the weapon's base power. Once it has been improved enough to cross certain thresholds, it may be built up into a stronger weapon with higher maximum ability.
• The Diablo series:
  • Diablo II allowed the upgrading of gems, either through the Horadric Cube or touching a gem shrine which would drop one of your gems on the ground as a higher level one (For example, touching a shrine while you have, for example, a chipped ruby would turn it into a flawed ruby). If you didn't have a gem, it would drop a random, chipped gem when activated.
  • Far more forgiving in Diablo III. Once you find your jeweler, Covetous Shen, you can both combine gems that drop from monsters and treasure hoards into higher-stat gems by using his Crucible, and you can have gems removed from weapons, armor and other items for a nominal fee, which is VERY helpful, because creating the higher-end gems becomes hideously expensive later on.
• In Digimon World 4, weapons and armor found in the field or available in the shop randomly generate with a number of mod slots. The player can add chips to raise stats, apply elemental properties, or produce other unique effects.
• Disgaea has Specialists, essentially NPCs that live inside items. Once a Specialist is subdued (by going into the Item World of that particular item and beating them up), they can be moved around to other items and even combined with other Specialists of the same type to power them up. Every item also has a number of slots to hold Specialists, with 'rare' and 'legendary' items generally having more slots than normal items.
• Divine Divinity refers to them as "charms". The difference here that the amount of charms you can put on a piece of equipment is determined by your Charms skill, in addition to the "Charm Quality" of the item.
  • Divinity: Original Sin II: socketed equipment is randomly obtained and can be enhanced with "runes", each of which has different effects depending on the equipment type to which it's added. Runes can be added and removed at will; the Item Crafting system also allows some runes to be fitted with "frames", which irreversibly creates a new rune.
• Dota 2 uniquely has this only for cosmetic effects. Fitting, as the items themselves are strictly cosmetic.
• Dragon Age:
  • The enchantment system in Dragon Age: Origins. Sandal can add or remove runes free of charge. The runes themselves come in different grades; the most powerful ones usually have to be bought (which is the case for most of the uber gear in this game). The Expansion Pack added armor runes, and a pyramid style (consuming weaker ones to make stronger ones) upgrade/crafting skill for them (that could be a Game-Breaker if you had enough money). Many players gave their weak ones to the mages/templars to strengthen their forces and get xp in the original campaign, then played Awakening and incidentally missed out on a lot of crafting opportunities.
  • In Dragon Age II, the enchantment system is revised, runes can no longer be removed from equipment once they are set in, but can be replaced by other runes. Thanks to the revised crafting system, this method is actually more cost effective than the system that was in place in the first game.
  • In Dragon Age: Inquisition, component upgrading is introduced for armor and weapons. Armor typically has arm and leg slots, while one-handed weapons typically have a grip/haft slot. Two-handers have an additional pommel slot. Bows have a slot for the hand grip, and staves have a slot for the shaft and the blade on the other end, and all weapons have a Rune slot. Bianca, Varric's one-of-a-kind crossbow, has the most of all with four; a bow limb slot, a grip slot, an aiming module slot, and a rune slot.
• EVE Online has "rigs" - modules that can be fitted to space ships' "rig slots" but can never be removed except by destroying them. Basically sockets and gems IN SPACE!. However, many rigs in EVE actually impart a penalty to one aspect of your ship, as well as the bonus to another one (for instance, increasing armor hp at the cost of a reduction in max speed). The various rigging skills reduce this penalty though.
• EXA_PICO:
  • Ar tonelico: Melody of Elemia: All equipment can be enhanced by placing Grathnode Crystals into them, each of which have different effects like adding elemental damage or increasing stats. Said crystals can also be applied to the Song Magic of the Reyvateils to make them hit more times or cost less MP.
  • Ar tonelico Qoga: Knell of Ar Ciel: The girls' Song Magic can be customized using fairies called Hyumas that aside of providing extra effects like buffs, elemental resistances and increase to the periodic healing in battle, also changes the battle music depending on how the battle goes.
• Referred to as "augments" in the Fable games. Ironically, most "Legendary" weapons come pre-slotted with enhancements, meaning the perfectly normal sword you found and slapped 6 enhancements on could theoretically (especially in the sequel) be more powerful than either of the Infinity Plus One Swords available. Taken to it's hilarious extreme with the most customizable and powerful weapon in the first game (provided you actually perform the sidequest necessary to find it) is a frying pan.
• Fate had NPCs who would give the option of either destroying a gem to free up a used socket, or destroying the item to reclaim the gem.
• Final Fantasy:
  • Final Fantasy VII and its various spinoffs have Materia, which is this trope without the mated-for-life aspect (as befits the Powers as Programs nature of Materia).
  • Final Fantasy X allows you to add abilities to weapons; its Green Rocks were generally consumable items (oddly enough, the required items had the opposite effect: poison items made poison-resistant armor and antidotes made poisonous weapons). This is done in blank slots of equipment, of which there can be four at most, so four abilities is the maximum (and most equipment you find has less due to having <4 slots and/or some slots already being filled with abilities). Any combination of abilities you find in one weapon, you can create in another, with a few exceptions in the game's Infinity Plus One Swords.
  • Final Fantasy XIV also has a materia system, although they work more like gems from World of Warcraft, providing small stat bonuses. Materia can be obtained by converting gear that has been equipped long enough to reach 100% "spiritbond"; higher-level gear has a higher chance of turning into higher-grade materia. These can then be attached to gear by a crafter of sufficient level, or by special "Materia Melder" NPCs (for a fee). Materia can be melded to gear beyond the number of allotted slots, but "advanced melding" like this has a chance of failure, resulting in the materia being destroyed, and cannot be performed by Materia Melder NPCs. Prior to Patch 3.2, high-end gear typically lacked materia slots entirely; nowadays, it simply disallows advanced melding. There is also a limit to how high materia can raise any given stat on a piece of gear.
  • Final Fantasy Crystal Chronicles: Echoes of Time has a forgiving gem system that works well with character customization. All equipment has one or more slots. Using equipment in battle increases its level. When it's level 3 it can be destroyed to produce a "Jewel". Jewels can be added and removed for a small fee. Some Jewels increase the level cap of equipment, and equipment produce two and three Jewels at levels 10 and 20 respectively. After beating the game for the first time, the player will have several Jewels and Armors to specialize their characters.
• Flyff allows you to make sockets in weapons & suits of armour (up to 10 & 4, respectively) for extra stat cards, although you need a CS item to keep the gear from breaking (you can put static bonus run speed or base stat cards in weapons, or % bonus HP/MP/FP/ATK/DEF cards in suits).
• Forever Home has Shards, which work a lot like Materia from Final Fantasy VII in that they can be duplicated after they accumulate enough PP.
• Freedroid RPG has up to 4 sockets on equipment and if there aren't, you may add them. Compatible add-ons can also be produced and vary with socket and equipment type.
• Geneforge implemented a simple version of this from the third game onwards, along with Item Crafting. Almost every item can take one and only one gem, with the exceptions taking no gems because they're so powerful anyway.
• Grand Chase has cards for weapons. Only rare weapons/Armor and Higher can be equipped with them. They can be removed with a (cash) item.
• Grim Dawn has components and augments that can be attached to items to grant stat bonuses, new skills, or proc effects. A piece of equipment can only have one of each type of item attached to it.
• All armor and most weapons in Guild Wars have upgrade slots. The weapons that don't (and those with missing slots) have built-in bonuses that are, usually, equivalent to max upgrades for the missing slots.
• Harvest Moon: Island of Happiness lets you do this with Wonderfuls, making this your method of upgrading your tools.
• Heroes of Ardania plays this trope absolutely straight, wherein the player can take many pieces of equipment to a "socket carver" to have sockets carved into his equipment. He may then place magical artifacts called "Dwarvern beard rings" into those sockets.
• Horizon Zero Dawn: Usually, outfits will have sockets available for protective weaves to be inserted into for extra protection against a chosen damage type. This, plus the fact that some modifications have multiple bonuses that overlap with the armor itself, means its possible to become immune (or near-immune, on higher difficulties) to a specific element or type of attack.
• Most gear in Iris Online has slots for up to 5 cards (which ones go in which slot is based on blood types).
• In Kingdom of Loathing, this is a special property of the Scratch n' Sniff Sword/Crossbow (comes with the power to summon stickers to put on it), the Fossilized Necklace (beat up skeletal enemies to get their teeth), and the Over-the-shoulder Folder Holder (find and acquire special stat-boosting folders to put in it).
• In Kingdoms of Amalur: Reckoning, some equipment has sockets for gems that can be added at a Sagecrafting altar. Putting points into the Sagecrafting skill allows a player to craft the best possible gems in the game. Investing points into the Blacksmithing skill allows a player to use gems as forging materials, negating the need to find equipment with sockets.
• The Orbments in all the games in The Legend of Heroes: Trails series have a set of slots for various Quartz. Which Quartz the player installs determine the stats and arts available to the character equipping the Orbment.
• Light Fairytale: The Orb system is similar to the Materia system of Final Fantasy VII. However, weapons and armor automatically gain the affinity of elemental orbs equipped to them.
• Mass Effect:
  • Mass Effect had weapon, armor, grenade and ammunition upgrades. While early weapons and armor only had one weapon and armor upgrade slot, it increased to two slots in more powerful versions. However, there was only one grenade launcher, which only had one grenade upgrade slot, and each weapon could only have one ammunition upgrade.
  • Mass Effect 2 "streamlined" this into universal (for class of gun a la sniper rifles) upgrade system, and ammo in the form of skill point costing ammo powers that were annoying to have to activate every level.
  • Mass Effect 3 brought the system back, though only for weapons and each weapon has exactly two slots. Any upgrade or "mod" fits the basic five weapon types and can be put into any number of these weapons at once. Multiplayer also has three additional slots that affect the entire character, but the upgrades are used up after a mission. These include ammo mods (replacing ammo powers from singleplayer), damage boosts and armor boosts (ranging from faster shield recharge to faster power recovery or run speed). More types were added over time, and there is now a fourth slot for non-expendable upgrades that do all kinds of things, like increasing grenade, consumable, and ammunition carrying capacity, and specific and combined damage bonuses for the whole range of character builds/equipment that got added in in patches.
• MapleStory allows players to use a device bought with mesos to add a socket to their each of their armor that they can put a Nebulite in to increase their stats. Nebulites can either be obtained through world bosses or you can get them through an item Gachapon.
• Mega Man:
  • Mega Man X5: X and Zero can equip two special parts after defeating the Mavericks that can be added to their armor.
  • Mega Man Battle Network: The Navi Customizer lets you socket Mega Man with programs that enhance his abilities. There are rules for customizing, and breaking the rules may result in Mega Man getting bugged.
• In the Monster Hunter:
  • Weapons, armor, and talismans each have zero to three slots that players can put decorations in to put points into a skill, which becomes active once enough points are added. Some of these decorations take away points from a different skill, which can activate a skill with a negative effect if enough points are taken away (for example, having enough negative points in a skill that boosts fire resistance will make you more vulnerable to fire-based attacks). Some decorations take up two or three slots, in exchange for providing a bigger boost than decorations that just need one slot.
  • Monster Hunter: World revamps the game's skill system, and consequently how decorations work. Decorations drop randomly after high-rank missions, and only high-rank armors and weapons have decoration slots, with the "beta" versions of armor pieces having fewer built-in skills than the "alpha" versions, but more decoration slots.
• In a rare non-RPG example, this is how card upgrades work in the deckbuilding roguelike Monster Train. Rather than cards having fixed stats for upgrades, they instead have two sockets that upgrade stones are applied to. A pair of Artifacts will add a third socket to every card of a certain type in your deck.
• Path of Exile:
  • The game inverts Diablo II's system: the skill tree consists entirely of passive skills, while sockets are used for active skills. Almost every equipment comes with sockets, which determine what combat skills you can use and what skill-enhancing gems you can link to it, making skill management some odd cousin of the Inventory Management Puzzle. The lack of equipment enhancement from socketing is compensated for by nearly everything being enchanted, and there being several ways to upgrade or add enchantments.
    • Also, gems very easily pop into and out of your equipment, and it's pretty much expected you shift your gems around into new spots if the gear you find has linked sockets that allow you to combine your gem-granted skills in new ways.
  • Path of Exile also has a socketed skill tree. Around the skill tree, there are slots to socket Jewels into, which basically serve as an enchantable passive node, which you can craft to optimize your character's stat bonuses. Unique jewels also interact with the skill tree, such as converting the stats of nearby passive skills to a different one, letting you allocate skills without directly connecting to them, and even upgrade active skills. More complex jewels can replace every passive skill within its radius with new ones, gain bonuses based on how it's connected to your skill tree, or add an entire passive skill cluster of your making, which can have its own jewel sockets.
• Looplets in Pokémon Super Mystery Dungeon are held items that have notches where you can insert Emeras to give a Pokémon perks such as stat boosts or the ability to Mega Evolve. However, they wear off upon exiting a dungeon.
• Ragnarok Online has slots in weapons and equipment for cards, which are rare drops from monsters.
• Ratchet: Deadlocked uses this. Each weapon has 10 slots for Alpha mods, which upgrade mundane things like firing rate, accuracy, and money, and one slot for an Omega mod, which adds an odd effect like napalm, electric shock, or morph.
• In Ravensword: Shadowlands, weapons and armor (some of them, at least) come with "Enhancement" slots, meaning that you can put gems into them that provide bonuses to either damage or your stats. However, there's also some other items like Spider Venom that you have to put into such slot in order to make use of it.
• Guns in Resonance of Fate all have various slots where you attach parts to increase their stats. The expansion parts themselves can have more slots to attach more parts and then those parts can have even more slots, leading to truly insane designs with multiple scopes, barrels and grips stacked on top of each other with no regard to what they're pointing at...in the end, only the size of the customizer's grid limits the amount of add-ons used.
• Sacred allowed socketing of up to four rings/amulets/runes or blacksmith abilities. You could recover only one of these, so if you found something useful early on most players socket that and fill the rest with the blacksmith powers. Dwarves could socket anywhere and and had specialist blacksmith powers.
• Star Wars:
  • Star Wars: Knights of the Old Republic: The game features "upgradeable" equipment that could be fitted with better components. In the first, armor and non-lightsaber weapons had only one "gem" per socket; all guns used the same scope, for instance, although some had different bonuses from it. In contrast, lightsabers not only had a wide variety of stat crystals for two slots (and a color slot), but also had two special color crystals (Mantle of the Force, and Heart of the Guardian) that changed the effects of absolutely every upgrade crystal, in two separate ways.
    • Star Wars: Knights of the Old Republic II – The Sith Lords featured a full range of different components for each slot; weapons had three slots apiece, armor had two, and lightsabers had five (although two were "crystal" slots that worked like in the first game) not counting their color crystal. Any given slot had between about three and six different types of upgrade, each with multiple levels. These can now be crafted, with a large variety of skill requirements, making your crew's skills more useful. The main character (only) can get a special crystal that changes effect with the player's alignment and level, but the specialness is reserved for that crystal alone this time.
  • Most types of weapons and armor in Star Wars: The Old Republic feature modification slots, which determine all of their stats (including how much damage weapons deal, how well armor protects, etc.). High-end gear contains more powerful mods, but all pieces of gear are just as effective when equipped with the same mods, and mods can be extracted from items for a nominal fee. Virtually all "special" items, including items sold through the in-game store, are empty modifiable gear, meaning players can use it with appropriate mods through the entire game.
• Primary Spirits in Super Smash Bros. Ultimate are equipment that boost the defense and (with one exception) attack power of whoever uses them and often grant one other change, such as increasing the power of certain types of attacks, increasing jump height, or, for a disadvantageous example, starting the fight with damage. Each one also has a number of slots, ranging from zero to three, allowing the player to also equip Secondary Spirits that give certain buffs, such as slowly healing over the course of the battle or starting the battle made of metal, but take up certain amounts of slots depending on the trait.
• Alchemists in Tales of Maj'Eyal can insert gems into armor, granting the gem's special bonus to the armor. Each piece of armor can only take one gem, and adding a new gem removes the old one.
  • The Embers of Rage expansion adds a system for crafting steampunk devices and attaching them to equipment to provide stat bonuses or a new ability.
• Tree of Savior follows Diablo's example—an uncommon drop from enemies (especially boss monsters), gemstones provide buffs (and penalties) depending on what kind equipment they're inserted into. Sockets must be first drilled into equipment before any gems can be inserted, though.
• Torchlight allows you to destroy either the weapon to retrieve the gems, or smash the gems to re-open the slot, averting the problem of having the Random Number God award you better loot just after you made a gem/socket commitment. Torchlight also allowed you to combine two identical gems into one that's a level better.
  • A Loading Screen tip in Torchlight II encourages you to use Ember and socketables when you find them since finding new equipment often coincided with finding better Ember. Although you can no longer transmute Ember into higher levels, you can transmute three socketables into a rare Ember with the grade being an average between the three.
• Vagrant Story has a variety of gemstones that Ashley can find and socket into his wepons and shields in order to change their properties.
• Warframe:
  • The game has a rather complicated mod system. Each piece of equipment gets eight slots (or ten, in the case of companions) that the player can use to equip mods. Need more health on your Warframe? Equip the Vitality mod. Want to add some Heat damage to your sword? Try using Molten Impact. However, every mod equipped uses up a certain amount of points, and the number of points available is directly tied to the level of the equipment in question; there are ways to stretch your points further than normal, but they require rare items and some effort. Since Warframes only get minor stat boosts from leveling up and weapons don't get any stat increases at all, modding is the only way to make your gear strong enough to take on the game's hardest challenges. Unlike most examples of this trope, mods can be freely moved around or removed between missions, and the same copy of a mod can be equipped to multiple items at the same time.
  • Most items that can be modded can also be socketed with an Orokin Catalyst or Reactor, which doubles its mod capacity, and a Focus Lens which converts excessive Affinity (experience points) into Focus points that can be spent on upgrades to its associated Focus school. There are also Exilus Mods, which have less important effects but can be equipped in a special slot (that must be unlocked with another item). Unlike mods, these upgrades are permanent and consume the associated item (although Focus lenses can be replaced with another lens, destroying the old one in the process).
  • Warframes have five Archon Shard slots, in which rare gem-like Shards can be socketed for further boosts. Like with mods, Archon Shards can be removed, but unlike them, this costs resources.
• World of Warcraft:
  • Socketed items were introduced in the first Expansion pack. Sockets come in three different colours (Red, Yellow and Blue) (plus Meta Gems and Prismatic Slots), gems come in 3 primary and 3 secondary colours (Red, Yellow, Blue, Orange, Green and Purple, as well as Prismatic) and you get a bonus for matching up the colours. Gems can be either found or cut by Jewelcrafters. The best Gems can also only be used by Jewelcrafters. Uncut gems cannot be placed in sockets (in a massive aversion of All-Natural Gem Polish).
  • Gems of secondary colors boost 2 stats, one from each of the primary colors that make it up, but by about half the amount as a primaries that make that color. They can also activate the sockets of either color that make it (Thus 2 Orange gems can give the same stat boost as a red gem and a yellow gem, but still counts towards the socket bonus if you have red slots.)
  • Meta Gems are special and only found on "Head" slot items. They require different combinations of gems in other sockets before they can be used but provide different kinds of stats. Also Prismatic Gems and Slots can fulfill/be fulfilled by any gem color.
  • Depending on the cut, color and type of gem/quality, the stats will differ. All red gems have the same dozen cuts that other colors can't be cut into, but the better the gem, the higher the stats increase.
  • Also, while gems cannot be removed from slots, they can be replaced by a different one, with the original one being destroyed.
  • Blacksmiths can also add slots to gear, the most common one (and only one usable by non blacksmiths) is a belt buckle that adds 1 prismatic socket to any belt.
  • There was originally no restriction on the item you could socket a gem into... and then after Wrath of the Lich King came out, twinks would socket Wrath-level gems onto Burning Crusade level gear (which had lower base stats but tons of gem sockets to promote the feature when it was introduced). Once Cataclysm was released, gems could only be socketed to equipment from the same expansion or later.
  • In Warlords the system has been greatly simplified. High level items will sometimes be generated with a single prismatic socket that takes any gem. High level gems no longer have color, and there is no meta gems. In this way it encourages players to continue keep killing bosses for that small chance an otherwise non-random item will drop with a socket and/or other bonuses.
• Xenoblade Chronicles:
  • Xenoblade Chronicles 1 includes socketed items that allow you to socket and unsocket gems without consequence to boost various attributes or give new ones entirely. Some items come pre-equipped with gems with the caveat that they cannot be removed. Certain gems can only be equipped in armor or only in weapons while some allow you to socket them in either one. Weapons can have up to three sockets while armor pieces can have only up to one and sometimes even the same weapon or armor piece can have more or less slots depending on the enemy that drops it.
  • Xenoblade Chronicles X uses a similar system to its predecessor with slots for augments. This time around, while there are equipment with pre-equipped augments, they don't fill up any slots, and a Randomly Generated Loot system allows for dropped equipment to have varying numbers of slots. After completing a mid-game sidequest, a shop that allows for adding additional augment slots is unlocked. However, there are some items that can't have any extra slots added.
• Xeodrifter has a non-RPG implementation. Picking up gun upgrades adds a point that can be freely moved between five categories: shot speed, shot power, rate of fire, shot spread (points into this add spread between shots), and shot waviness (points into this make shots move in a sine wave pattern). Power upgrades need 2 points to improve their effect, everything else needs just one point per slot.

Non-Video Game Examples

• Dungeons & Dragons 3.5:
  • The Magic Item Compendium supplement introduces Augment Crystals, which can be attached to your weapons or armor to provide bonuses. The item doesn't need an explicit "socket" for these crystals, but only one can be used at a time, and more powerful crystals only function when attached to a correspondingly powerful piece of equipment. Their advantage is that you can transfer the crystals to new items when you upgrade your equipment, so even if they aren't very powerful on their own, they never really become obsolete either. Some of these crystals also double as an Obvious Rule Patch, allowing effects which are useful but niche (such as summoning your weapon from a short distance or letting it damage ghosts) to be accessible to players at a fixed cost, rather than the exponentially-scaling costs for adding these properties to magic weapons and armor directly.
  • Eberron supplement The Forge of War has Dragonshard Pommel Stones, which can be enchanted with the properties of a magic weapon and then grant these properties to any weapon they are attached to. Generally considered Awesome, but Impractical since they cost double the price of a normal magic weapon, and attaching one disables any magical properties the weapon had already.
• Edge of the Empire: Every weapon has a limited number of hardpoints that can be used to install improvements (underbarrel flamethrower, scope, etc.), and some Technician careers allow you to add more of them to weapons.
• Many artifacts in the role-playing game Exalted have slots for hearthstones, which can be used either to regain Essence (common trait for all hearthstones) or to utilize a power unique to the stone.
• In Pathfinder 2nd edition weapons and armor can be engraved with runes that can be transferred from one compatible item to another, or temporarily stored on a runestone. Runes are divided into Fundamental and Property runes. There are only four Fundamental runes: Armor Potency (increases armor class) and Resilience (improves saves) for armor, Weapon Potency (adds to attack rolls) and Striking (multiplies damage) for weapons, an item can only have one of each but they can be upgraded to stronger versions. Property runes add special qualities to the item such as elemental magic or the ability to harm ghosts, but an item can only hold as many Property runes as the bonus granted by its Potency rune (i.e. a sword with a +2 Weapon Potency rune can have two Properties).
• Parodied in Sluggy Freelance in its "Years of Yarncraft" parody of World of Warcraft. Items could have sockets for rather random items like blenders, and some headgear was headgear-socketable, meaning you could have your old hat socketed onto your new hat.

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