Bombs are throwable items that destroy nearby blocks on contact. This includes Lair or Dungeon blocks.
They are dropped uncommonly from destroying grass in the world and killing enemies, and can be crafted at the Adventurer’s Crafting Bench.
Bombs can be used during Challenges or when filling Tomes and the Star Bar to reduce the amount of time needed to complete the quest by removing obstacles.
Bombs have a variant called the Big Bomb, which has a wider radius, more powerful destructive force (destroying any block with a single blast), has a short fuse before detonation and cannot destroy dungeon blocks.