Books

There are two types of books in Vermintide; Tomes and Grimoires. Each provides an improved die, replacing one of your dice in the final roll of Ranald's Bones. In addition to Books, you can also sometimes find a Cursed Die within a mission. Books are usually hidden in out of the way places and require exploration to find, however, tomes and Grimoires always spawn in the same location in each map.

Tomes
The Tomes are an item found in many of the missions in Vermintide. The Tomes are found in set locations within the main missions of the campaign, usually three per mission. A Tome takes the slot for your healing item. Tomes can be set down and picked up by other players with no consequence.

Each Tome replaces one of your dice with an improved die. If players complete a mission while carrying a tome in their item slot, all players have one of their loot die boosted in quality (the die will have 4 "success" faces instead of the normal 2).

Grimoires
The Grimoires are item found in many of the missions in Vermintide. The Grimoires are found in set locations within the main missions of the campaign, usually two per mission. A Grimoire takes the slot for your potion. Grimoires cannot be set down, and clicking while the Grimoire is selected will cause it to be discarded permanently. Grimoires are dangerous to carry and reduce the max health of all players by 30%. This effect stacks up to 60% max health reduction.

Holding a Grimoire when completing a mission rewards the player with a Grimoire die. If players complete a mission while carrying a Grimoire in their item slot, all players have one of their loot die boosted in quality (the die will have 6 "success" faces instead of the normal 2, thus guaranteeing one success).