Per-target contact cooldown

What it is

Per-target contact cooldown is the re-hit gate used by orbiting and tethered melee-style weapons: a single weapon bullet can hit the same enemy at most once every N seconds, where N is configured per weapon. It allows blades that physically stay in contact with an enemy across many frames (orbiting swords, rotating electricity tethers) to deal a clean rhythmic tick instead of a per-frame DPS blast, while still letting them re-strike the same target on each subsequent pass.

How it works

Each affected bullet carries its own per-enemy cooldown map. On every collision check, the weapon looks up the candidate enemy in that map and skips it if it was hit too recently.

Step	Behavior
1	Bullet spawns with a per-enemy cooldown map and a configured cooldown duration
2	Each frame, the bullet checks every nearby enemy for a hitbox overlap
3	If the enemy appears in the cooldown map and its remaining cooldown has not elapsed, the hit is skipped (no damage, no VFX)
4	If the enemy is not on cooldown and the hitbox overlap holds, the weapon damages the enemy and writes a new cooldown entry for that enemy
5	Cooldown either ticks down each frame (tether-style) or is compared against the bullet’s running age (orbit-style); once the gap exceeds the cooldown duration the enemy becomes hittable again
6	When the bullet is recycled back to the pool, its cooldown map is cleared so the next bullet using that slot starts fresh

The cooldown is per bullet, per enemy — two different blades from the same weapon do not share cooldown maps, so a target sitting between two orbiting blades takes one hit from each per pass.

Default cooldown

If a weapon’s spec omits the field but its behavior reads it, the engine substitutes a default value rather than allowing infinite-rate damage.

Quantity	Value (seconds)
Default cooldown when spec omits the field	0.3

Which weapons use it

Four weapons consume the spec field directly; their cooldown is wired through the bullet’s per-enemy contact map at spawn.

Weapon	Rarity	Behavior	Cooldown (seconds)
Sweep	epic	orbit	0.18
Fire Ring	rare	orbit	0.18
Line	epic	tesla_line	0.08
Magnetar	epic	tesla_line	0.08

One additional weapon defines a cooldown in its spec but its behavior does not consume the value — its arc dies on first contact instead of re-hitting.

Weapon	Rarity	Behavior	Spec value	Effective re-hit gate
Barrier	uncommon	shield_arc	0	Not used — bullet despawns on first hit

The Star Halo legendary uses a different re-hit gate (one full revolution between hits, derived from spin duration ÷ spins) rather than the per-weapon cooldown field. See weapons for the legendary’s spin model.

EXTRACT-CANDIDATEs

• EXTRACT-CANDIDATE: orbit blade swept-arc hitbox model (prev-angle vs current-angle sweep delta, radial + angular-half-width check, tip-extension buffer) — a distinct concept from the cooldown, shared by Sweep and Fire Ring.
• EXTRACT-CANDIDATE: tesla-line segment hitbox model (point-to-line-segment distance with line-thickness fudge, midpoint spatial-grid query) — shared by Line and Magnetar.
• EXTRACT-CANDIDATE: bullet-pool recycle contract (which fields the pool nulls on release vs which are reset at spawn) — load-bearing for any per-bullet state, was the source of a Sentry crash when the orbit blade init guarded on the wrong field.
• EXTRACT-CANDIDATE: spawn-immunity window (_spawnT > 0.15 skip used by every contact-cooldown behavior) — a global rule that newly-spawned enemies are uncollidable for ~150 ms; deserves its own page.
• EXTRACT-CANDIDATE: ship contact cooldown (the enemy-side cooldown on touching the player, separate from this bullet-side cooldown) — same name, different system; worth disambiguating on a combat page.
• EXTRACT-CANDIDATE: Star Halo revolution-based cooldown (cooldown = spinDuration ÷ spins, applied per star × enemy) — a sibling re-hit gate used only by the legendary orbit-ring behavior.