Sentient Meat Hook

The Sentient Meat Hook is an item in Risk of Rain 2.

This item stacks hyperbolically in on-hit chance to fire hooks and linearly in number of hooked enemies.

Math
The actual chance for the Sentient Meat Hook to proc is not additive as the text suggests, but is instead calculated by $$100 * n / (n + 5)$$, where n is the stack size. This means that additional Sentient Meat Hooks provide diminishing returns, and amassing a stack large enough to guarantee a proc on nearly every attack is impractical.

The hooks themselves have a Proc Coefficient of 0.33.