Creep combat effects

Authored contracts

Checked with ability_audit -raw against ROC and TFT. AbilityMetaData.slk and UI/WorldEditStrings.txt resolve the radius/damage field labels.

Ability	Fields and behavior
Disease Cloud Aapl, Aap1–Aap4	DataA infection lifetime (120 seconds), DataB DPS (1), Area acquisition radius. Aap4 has zero damage. ROC omits BuffID; TFT uses Bapl (and cloud presentation Bplg). Infection remains after leaving the source.
Pulverize Awar, ACpv	DataA percent chance, DataB damage, DataC full-damage radius, DataD half-damage radius. Area is zero. ROC/TFT Awar uses 25/60/250/350.
Incinerate ANic, ANia	TFT only. DataA stacking bonus; DataB/C full explosion damage/radius; DataD/E outer damage/radius; DataF explosion delay. Area is zero. BNic lasts Dur. Any lethal source while marked triggers the explosion once.
Web Aweb, ACwb	Air-only enemy spell. DataA landing/rising time, DataB starting height, DataC bound melee range; Dur/HeroDur lifetime. TFT BuffID is Bwea,Bweb; ROC omits it and uses the known WebAir token. Shares Ensnare's bind/height mechanism and restores flight after the last bind.
Monsoon ANmo, ACmo	TFT only. Fixed selected point, Area radius, DataA damage, DataB interval, DataC building damage factor, Dur channel lifetime. Moving/cancelling the caster ends the channel.

Ownership and persistence

Disease Cloud and Incinerate live in their ability modules. Generic status tick/death messages dispatch through the applying rawcode. Source identity, rank and tick deadline travel with the status; source pointers use the save schema's entity fixups and incarnation checks reject reused slots. The Incinerate mark is installed before attack damage so ordinary lethal hits and other damage sources reach the same death callback. Its delayed explosion uses an ability-owned, save-rostered thinker at the death position.

Web delegates its bind lifecycle to Ensnare; the shared height updater runs once per unit. Both buff families participate in last-bind restoration. Monsoon owns a fixed-point channel thinker rather than borrowing Bladestorm's caster-following thinker.

The Web procedure handles A_AUTOCAST_ON/A_AUTOCAST_SET through CAbilityModalSpell; AB_AUTOCAST and acquisition alone do not enable its command-card toggle. Save tests must install the flyer's UnitData row, since load rebinds immutable tables and deliberately discards stack-backed test rows.

Source removal/incarnation changes invalidate pending damage; a living or dead source in the same edict incarnation remains valid for an existing infection or mark. New status pointers are F_EDICT fields, and the new thinkers are appended to save_cfunctions[]. The enlarged edict record rejects older saves through the existing save-header size check.

This does not implement Plague Toss (Apts): it is a separate attack-triggered cloud producer, with zero Area/DataA/DataB and TFT UnitID uplg, not an aura row. Incinerate Arrow's separate mana/autocast policy and complete target-mask semantics remain outside these combat-lifecycle fixes.

Verification

t_creep_regression.c covers the six PR #479 failures through attack/cast and scheduler entry points, with stock zero Area cells. Further cases cover outer rings, expiry/dispel, source invalidation, off-origin channels and save/load.

make test-wc3-engine WC3_PATTERN='wc3_spell.creep_regression*'
make test-wc3-engine WC3_PATTERN='wc3_save.creep*'
make test

The original tests supplied damage in Disease Cloud's duration cell and invented nonzero Area cells for Pulverize and Incinerate. These fixtures must retain the authored column meanings even when numerical values are customized.

See also creep aliases, Ensnare, save/load, and attack damage.