Set-up a 2 player multiplayer game with the following settings:
Rules: Battle Royale
Player: 4P
COM Level: Off
Sets: 1
Time: 9
Start Position: Fixed
Revenge Carts: On
Pressure Blocks: On
Skulls: On
Special Abilities: On
Pick 'Pitfall Zone' & any Bomber Types for controllers 1 and 2 then select 'None' for the other two player slots.
When the game starts, begin dropping bombs next to all the blocks in the arena, picking up all the power items that spawn as you go along. You will need to pick-up 7 Bomb items to unlock the achievement.
When the achievement unlocks, drop a bomb on yourself to also get: