Here is the full list of all 15 Explosionade achievements.
Shoot 3 grenades out of the air without dying.
Destroy a platform with a Horronym corpse on it.
Revive yourself to full armor from 1 armor bar.
Beat a combat room without taking damage.
Touch the top of the room with your shield.
Kick 20 Horronyms without dying.
Stomp 5 Horronyms without dying.
Destroy the platform a Clinger is on.
Kill a Bezerker.
Achieve terminal velocity by shield bouncing.
Complete Chilled Campaign.
Complete Normal Campaign.
Complete Serious Campaign.
Collect 20 pieces of gold in one life.
Beat the game without dying.