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Item
Dangerous Bunny is an in-game item that can be bought from a Shop or can be found in a Crate. Most Items modify the Stats of the player, and some of them provide additional effects.
Dangerous Bunny
Dangerous Bunny gives you +1 Free reroll in the Shop for each bunny you have. So if you have 3 Dangerous Bunnies, you can reroll the shop 3 times for 0 Materials each shop. The free rerolls doesn't increase the price of subsequent rerolls, so the price of the 4th reroll is unchanged. It costs the same as if it was your first reroll.
Buying all 4 items in the Shop reduces the cost of the current reroll to 0. However unlike the free rerolls from Dangerous Bunny, the price of the next reroll is still increased.
However, when you buy a Dangerous Bunny in a shop, it reduces the cost of the current reroll, instead of granting a "free rerolL".
See Shop Rerolling