Legacy (传承 / Heritage) — Bond Tier Boost

How equipment Legacy works: when a piece of gear has the Legacy flag set (in-game UI: [传承] / [Legacy] prefix on the gear name + gold border sprite), every one of its 3 bond slots gains an additional +1 to its level.

Source: decompiled EquipHelper.GetEquipBond and EquipHelper.SetEquipHeritage in data-session/intermediate/decompiled_equip.cs. The math is in MainScripts.dll (HybridCLR HotUpdate), not in any DataTable.

What Legacy DOES

Bond level +1 for all 3 slots (Pure / Title / Enhance), capped per-bond by the bond's max tier (= number of comma-separated entries in BondDataTable.Value1, e.g. Sharp/Sturdy = 6 tiers max, Fair Trade = 2 tiers max).

The bonus stacks on top of the star-up bonus:

State Pure Title Enhance
★0, no Legacy base base base
★3, no Legacy base+1 base+1 base+1
★0 + Legacy base+1 base+1 base+1
★3 + Legacy base+2 base+2 base+2

(MaxLevel cap applies at every step.)

What Legacy does NOT do

Legacy does NOT modify raw stats. Verified by full grep of Heritage references in decompiled C# — 8 references total, none inside GetEquipAttr (the function that computes raw STR/INT/DEX/CONS/SPD/Luck/Tough/Mana). All 8 references:

Line Where Effect
557, 645 UI init Set/clear flag
656 UI title Show "[Legacy]" prefix on gear name
1209 UI preview Display "+1" or "+2" in bond text
1568 GetEquipBond +1 every bond level (capped by MaxLevel)
1582 SetEquipHeritage(step) RNG roll on drop
1906 UI sprite Border sprite (gold vs default)
2642 Serialization JSON property declaration

The localization text "Legacy adds one more stat" (Battle_Option_Travel_09) is misleading — it's a translation of CN 传承会使装备拥有的词条数+1 ("Legacy makes gear's 词条 count +1"). 词条 here refers to bond entries, not raw stat lines. The EN translator picked "stat" because 词条 is ambiguous, but the code path only modifies bond levels.

How gear becomes Legacy

EquipHelper.SetEquipHeritage(string step) rolls RNG when gear drops. Drop probability scales with rarity:

Step Legacy roll chance
C 1/160 ≈ 0.625%
B 1.25%
A 2.5%
S 5%
SS not implemented in this code path (SS items use a separate flow; verify in-game)

(Constants from EquipHelper.SetEquipHeritage switch.)

So Legacy is purely a drop modifier — there's no in-game upgrade UI to convert a non-Legacy piece into a Legacy piece. You either roll Legacy at drop time or you don't.

Note: Items_Des_D00007_* loc keys describe a "Legacy Stone" item that "allows gear of the corresponding tier to gain Legacy", which would be a UI-driven legacy upgrade. The corresponding code path was not located in the current decompile dump — likely in a service handler not in EquipHelper. Treat the RNG drop chance as the primary path for now; if the user reports gaining Legacy via Stone, re-check after next decompile.

Implementation notes

Cross-refs