From Brotato Wiki
Pile of Books
Item
Tier 3
Stats
Your structures can crit
+3 % Crit Chance
+3 Engineering
+3 % Crit Chance
+3 Engineering
Price
70
Limit
1
Item
Pile of Books 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.
Unique
Pile of Books is a unique item. Only 1 of each unique item can be equipped, and it will then no longer be offered in the Shop, and no longer drop from loot crates.
Notes
Pile of Books makes your Crit Chance stat apply to Structures including 
Landmines. Structures have a base 0% Crit Chance compared to the standard 3% that most Weapons have.
Pile of Books can be hard to make work in regular mode, since some engineering items reduce Crit Chance: 
Compass and 
Pencil . But is amazing for Endless Mode, where it lets you trigger 
Hunting Trophy.
Update History
- 1.1.0.0: Added to the game.