Bosses

The Thorium Mod expands on the number of bosses that can be challenged at different points in the game, featuring unique drops and AI, making every encounter a memorable one. Most bosses do not spawn naturally on their own, and thus require their respective boss summoning item to initiate the fight.

In Expert Mode, bosses drop Treasure Bags which contain exciting Expert Mode exclusive items. These include, but are not limited to: the Omega Drive, which summons a pet that is able to attack; and the Dormant Hammer, a key component in the ultimate weapon of the mod, Mjölnir.

Defeating these bosses are not required for game progression, but may be beneficial as they can provide useful items and access to new Town NPCs. Defeating The Primordials, a post-Moon Lord boss, grants new end-game equipment that overpowers some of the vanilla end-game content twice over.

Similar to vanilla Terraria, players that are under prepared may find bosses challenging, and players that are over prepared may find the boss fight too easy. Hence it is up to the player's discretion to adjust the angle at which they tackle the different bosses, ensuring they are able to enjoy fighting them to the best degree.