Simultaneously Kill 6 Enemies with a Single Bomb

Bombs are purple glowing fruit you can find hanging in the environment. You'll play a tutorial and learn about them the first time you find a breakable wall. Lure at least 6 enemies toward a bomb and hold Y to pull the bomb with dust storm. Best done in chapter 1 as the enemies have less health and more likely to die in one hit from a bomb.

There's a bridge in Abadis Forest that you cross as part of the story. There's 3 bombs in this area, along with many Avees (flying monster) that you can kill for the achievement. If you don't get it your first try, you can leave the area and the monsters & bombs will respawn.