Soul Binding is the system in Aion 2 that stamps extra stats onto a piece of gear, and it is where a lot of your real character power comes from. It adds attack, defense, and even bonus skill levels on top of an item’s base stats, and it gives you three separate tools to push those stats higher or swap out the ones you do not want. The trade-off is simple. The moment you bind an item it locks to your character and can no longer be traded.
Quick answer: Open Enhance All, pick the Soul Binding tab, then use Bind (Soul Codex plus Kinah) to raise stat values, Sync to reroll one stat with duplicate gear, or Reset to reroll every stat at once.
How many stats a piece can hold
The number of Soul Binding slots on an item is fixed by its grade when you acquire it. Which stats land in those slots is drawn at random from that slot’s pool, and binding only changes how high they climb, never which ones you get. If the rolls are wrong for your build, Sync and Reset are the only ways to change them.
| Grade | Soul Binding slots |
|---|---|
| Common | 1 |
| Rare | 2 |
| Epic | 3 |
| Unique | 3 to 5 |
| Heroic | 4 to 6 |
Unbound Rare and Epic gear sometimes drops as loot you can still sell on the market. Once you bind it, that option is gone, so only commit to items you plan to keep. Unique and Heroic pieces also support one extra slot beyond the counts above, which is unlocked separately.
The three Soul Binding operations
All three tools live on the Soul Binding tab inside the Enhance All window. Each one does a different job, so the usual workflow is to fix the stats first with Sync or Reset, then raise them with Bind once they match your build.
Bind: raise your current stats
Bind pushes the values of the stats already on your gear toward their ceiling. Every bind is a guaranteed increase by a random amount, and as the stats rise, the item’s Soul Binding Rate climbs with them. When that rate hits 100%, the stats are maxed out. Each attempt costs 30,000 Kinah plus one or more Soul Codex, and the codex count grows as the stat gets closer to its cap.
Only max out items whose rolls are already perfect for your build. Once a piece reaches 100%, it drops out of the editing window and you can no longer change its stats.
Sync: reroll one stat
Sync replaces a single stat you dislike. You select the stat on your target item, feed in a sacrifice piece of the same grade and type, and the game rolls that one slot into something new. This is why you should never dismantle spare Unique drops. They are the fodder that fuels Sync. You can also use a Sync Stone Fragment in place of a duplicate item.
A Sync Stone below the gear’s grade applies only 10% of the time, so never sync Unique stones into Heroic gear. Double-check the target before you commit, because the sacrifice item is destroyed either way.
Reset: reroll every stat
Reset shuffles all the stats on a piece at once and resets its Soul Binding Rate. It needs a Soul Codex: Reset plus Kinah, and because the results are fully random, you cannot choose or guarantee any specific stat. Save it for a high-value item that you intend to keep but that rolled badly across more than two slots. In that situation, a full reroll is usually cheaper than burning another whole item through Sync.
Materials and where to get them
Soul Binding is one of the biggest resource drains in the game, so it helps to know where each item comes from before you start farming.
| Material | Used for | Where it comes from |
|---|---|---|
| Soul Codex | Bind | Dungeon drops, Expeditions, Dimensional Invasion, Shugo Festival, Nightmare shop, Hidden Cubes, Trade Shop |
| Soul Codex: Reset | Reset | Nightmare shop, quest and achievement rewards, seasonal trade shops, Hidden Cubes |
| Sync Stone Fragment | Sync | Sanctuary, dungeon morphs, or any spare Unique piece |
| Philosopher’s Stone | Extra slot | Conquest dungeons |
You do not need to touch Soul Binding while leveling. The main story keeps handing you fresh gear, so spending these materials early just wastes them. Hold off until you hit the level 45 cap before investing heavily.
Unlocking the extra slot with Philosopher’s Stones
Unique and Heroic pieces can add one more stat slot, but only after every existing slot is maxed, which is exactly what puts the item at 100% Soul Binding Rate. From there, the unlock costs 2 Philosopher’s Stones and 1,000,000 Kinah and always succeeds. There is no RNG on the unlock itself.
Both stones are spent two at a time, and roughly four pieces in five call for Philosopher’s Stone: Revelation while the rest need Philosopher’s Stone: Power. Which one an item needs is stamped on the item and cannot be guessed from its grade, tier, or item level, so two Unique boots at the same level can want different stones. Check the piece before you farm for it.
What carries over when you replace gear
Unlike manastones and theostones, your Soul Binding stats follow the item through a transfer. When you move enhancements to a new piece, every base stat carries over at the exact value you bound it to.
| On a transfer | Result |
|---|---|
| The base stats at their bound values | Carry over |
| The Philosopher’s Stone extra stat | Does not transfer |
The only exception is the extra slot unlocked with Philosopher’s Stones. It is re-rolled from scratch on every new piece, and the stones must be spent again each time. Because the base work is preserved, Soul Binding is worth doing even on gear you plan to upgrade later.
Which stats you can roll
Each slot draws once from a pool that depends on where the item is worn. About one draw in five lands on a class skill instead of a stat, granting it +1 level, and the available skills are tied to your class. Weapons, guards, and rings draw from the 12 active skills your class uses with that weapon, while armor, earrings, and necklaces draw from its 10 passives. Weapons are class locked, so a dagger only ever rolls assassin skills.
The other four draws in five land on a stat. The percentages below are the odds within that stat draw, so each table totals 100%. Read the numbers as a rarity ranking. The scarcest rolls are the strongest ones, which means a 2% Damage Boost on a weapon is the prize and an 8% HP roll is filler.
Weapon stat pool
| Stat | Chance | Stat | Chance |
|---|---|---|---|
| Accuracy | 8% | HP | 8% |
| Critical Attack | 8% | MP | 8% |
| Attack | 7% | Multi-hit Chance | 6% |
| Back Attack | 7% | Might | 6% |
| Block | 7% | Precision | 7% |
| Critical Hit | 7% | Combat Speed | 4% |
| Frontal Attack | 7% | Status Effect Chance | 4% |
| Weapon Damage Boost | 4% | Damage Boost | 2% |
Armor stat pool
| Stat | Chance | Stat | Chance |
|---|---|---|---|
| Block | 6% | Accuracy | 5% |
| Critical Damage Defense | 6% | Back Defense | 5% |
| Critical Hit Resist | 6% | Critical Hit | 5% |
| HP | 6% | Defense | 5% |
| MP | 6% | Evasion | 5% |
| Natural HP Regen | 6% | Frontal Defense | 5% |
| Natural MP Regen | 6% | Attack | 4% |
| Constitution | 4% | Dexterity | 4% |
| Willpower | 4% | Status Effect Resist | 3% |
Each armor slot also adds five stats that appear nowhere else. A few of these are worth planning builds around. Chest is the only armor source of Damage Boost, Shoulder the only source of Critical Damage Boost, and Gloves the only armor source of Combat Speed. Smite rolls on the helmet and cape only.
Accessory stat pool
| Stat | Chance | Stat | Chance |
|---|---|---|---|
| Natural HP Regen | 10% | Natural MP Regen | 10% |
| Block | 9% | Critical Hit Resist | 9% |
| HP | 9% | MP | 9% |
| Accuracy | 7% | Attack | 7% |
| Critical Hit | 7% | Defense | 7% |
| Evasion | 7% | Flight Power | 5% |
| Intelligence | 4% |
How the Soul Binding Rate climbs
Every Bind raises one stat toward its ceiling, and two things decide the outcome. The first is which stats you have, set when the gear was acquired and changeable only by Sync or Reset. The second is how high each one binds, where every attempt is a guaranteed increase but the higher values get progressively less likely.
Take a Unique dagger whose Critical Attack sits at 48 with a ceiling of 51. Each bind costs 30,000 Kinah plus Soul Codex, and the codex count rises as the stat nears its cap. When the game picks a value, each step up the ladder is rarer than the last.
| Critical Attack value | Chance of binding to it |
|---|---|
| 49 | 42.33% |
| 50 | 32.60% |
| 51 | 25.07% |
Longer stat ranges taper far harder. On the same dagger, HP runs from 226 to 265, and the very top of that range binds at just 0.65%. You will know a bind worked when the stat’s yellow bar advances and the blue Soul Binding Rate ticks up with it. Keep feeding codex into your best-rolled gear until that rate reads 100%, and the item’s stats are locked at their maximum.
