Crimson Rites (Thaumcraft 6)

The Crimson Rites are an item added by Thaumcraft 6. When used, they will add 50-100% observation progress and 33-50% theory progress in Golemancy, as well as 50-100% observation progress and 33-50% observation progress in a random category, but can be only used if the user has at least combined 20 normal and permanent Warp. In addition, they add 5 temporary and 1 normal Warp to the user, and have a 50% chance to add 1 permanent Warp as well. They can be also used in theorycrafting for 15-20 Eldritch and 10-15 Auromancy progress. They are also required to unlock the Eldritch tab in the Thaumonomicon.

Crimson Rites are rarely (1.25% + 1% per each Looting level) dropped by Crimson Knights, Crimson Clerics, and other cultist entities when killed by a player. There is also a player progression-based chance for each cultist to drop the item (two books can drop from one mob):
 * If the player does not already have a Crimson Rites in their inventory, and the player has scanned a Cultist (Crimson Knight, Cleric, or Praetor) with a Thaumometer, the drop chance is 25%.
 * If the player does not have a Crimson Rites and has not scanned a Cultist, the drop chance is 5%.
 * If the player already has a Crimson Rites in their inventory, the drop chance is 2%.