On use, Isaac throws a D2 into the air a short distance towards the direction he is moving which begins to spin on its edge like a coin while on the ground, drifting around in random directions, before shattering after a few seconds. The spinning D2 will reroll any pickups or monsters that pass through it, and any of Isaac's tears that pass through the D2 will gain random tear effects.
Monsters will be rerolled into those that have a similar amount of HP, identical to the effect of Dusty D10.
Isaac's tears that are rerolled by the spinning D2 will have the same possible effects as those from the D3 (see the tear effect list).
Items, opened chests, bosses and enemies' projectiles cannot be rerolled.
Notes
Isaac's tears, after being rerolled by the spinning D2, cannot be rerolled again, but the D2 can reroll pickups and enemies multiple times when passing through them more than once.
Only regular tears can be rerolled by the D2; it will not reroll any of Isaac's other weapons he fires such as lasers or bombs.
Dusty D10.
D3 (see the tear effect list).
Car Battery: D2 throws 2 dice on use.
Eternal Car Battery: D2 throws 3-5 dice on use.
Dire Chest item pool, according to Happyhead, is "because it's purple".
