Predatory Instincts Risk of Rain 2

"Critical strikes increase attack speed by 12%. Maximum cap of 36% (+24% per stack) attack speed." Green uncommon item unlocked via the Rapidfire challenge. Grants +5% crit chance (undocumented). On each critical hit, gain a 3-second buff stack of +12% attack speed. First item caps at 3 buff stacks (36% max). Each additional Predatory Instincts raises the cap by 2 stacks (+24%). Buff duration scales with proc coefficient. Additional items do not add more crit chance.

Each crit adds one buff stack, each stack gives +12% attack speed for 3 seconds. Critting adds a stack. Critting again before it expires adds another stack. At max stacks, each new crit refreshes the 3-second timer. At 100% crit the buff stays at max stacks permanently since you are always critting.

The item description "stacks 3 times" refers to the buff, not the item. This is the most common misconception. The in-game text means the Attack Speed On Crit buff can have up to 3 stacks. The item itself can be stacked as many times as you find it. Additional Predatory Instincts do not add crit chance but raise the buff stack cap by 2, enabling higher maximum attack speed.

Only the first Predatory Instincts gives crit chance. The +5% crit is not shown in the item description and does not stack. One item = +5% crit and 36% max attack speed. Two items = +5% crit (same) and 60% max attack speed. Three items = +5% crit and 84% max. Crit chance must come from Glasses, Shatterspleen, Harvester's Scythe, or other sources.

Buff duration is multiplied by proc coefficient. The 3-second base duration is scaled by the proc coefficient of the triggering attack. An attack with 0.5 proc coefficient that crits gives a 1.5-second buff stack. Attacks with 1.0 proc coefficient give the full 3 seconds. Low proc coefficient attacks like Ukulele (0.2) give very short duration buff stacks that are hard to maintain.

More attack speed means more crits per second, which keeps the buff at max stacks. This is the item's self-reinforcing loop. Crits give attack speed. Higher attack speed means more crits per second. More crits per second refreshes the buff more frequently. At 100% crit with reasonable attack speed, the three buff stacks are permanently maintained with constant timer refreshes.

Harvester's Scythe and Shatterspleen each give +5% crit alongside Predatory Instincts. All three items give +5% crit. Together they total +15% crit before any Glasses. With 9 Lens-Maker's Glasses adding another +90%, you hit 100% crit and the Predatory Instincts buff stays at maximum permanently for the entire encounter. The three items form the core of every dedicated crit build.

Laser Scope doubles crit damage, making every Predatory Instincts stack more impactful. More attack speed from Predatory Instincts means more crits per second. More crits per second means more Laser Scope doubled-damage hits per second. The two items multiply rather than just add - higher attack speed directly scales the DPS output of Laser Scope's crit damage bonus.

Plasma Shrimp generates more missiles per second with higher attack speed. Plasma Shrimp fires one missile per hit. Predatory Instincts increases hits per second. More hits = more missiles. With Transcendence ensuring permanent shield, every Predatory Instincts stack directly multiplies Plasma Shrimp missile output. The attack speed and missile synergy compounds strongly on high-speed survivors.

57 Leaf Clover improves crit roll reliability, keeping the buff active more consistently. At sub-100% crit, Clover re-rolls failed crit attempts for a favorable outcome. Higher effective crit chance means the Predatory Instincts buff stacks are maintained more consistently between 100% crit breakpoint builds. Particularly useful in the mid-run before reaching full Glasses stacks.

Purity reduces crit chance and destroys Predatory Instincts value. Purity rolls random effects for an unfavorable outcome - meaning crits become rarer with Purity active. Predatory Instincts requires frequent crits to maintain the buff. Fewer crits = fewer buff refreshes = buff expires constantly = near-zero attack speed benefit. Do not combine these two items.

Reach +200% attack speed at any point during a run

The +200% threshold is checked against your total attack speed increase, not base. A survivor with 100% base attack speed who gains +200% meets the requirement. The challenge completes the moment the threshold is crossed - even briefly during a War Horn buff.