Coolness is a stat that is increased by having specific items. Coolness reduces the cooldown of active items up to 50% and increases the chance of receiving a reward (such as a pickup or chest) upon clearing a room. It also decreases the chance for a chest to have a fuse by 2.5% per point in coolness.
The chance of the player earning a reward after clearing a room starts off at (1+{coolness}-{curse})%, and for every room cleared without getting a reward, it increases by a fixed amount (approximately 9% in a normal single-player run), up to a maximum of 80%. When a reward is dropped after clearing a room it goes back to (1+{coolness}-{curse})%.
Items that increase coolness include:
- Ballot
- Cigarettes (increases coolness by 1 per use)
- Heart of Ice
- Ice Cube (increases coolness by 3)
- Magic Sweet
- Old Goldie
- Shades's Revolver
- Sixth Chamber