Implosions

When a square block of 4 Dead-Ends is formed, this area is known as a possible Implosion.

AFTER a Monster is defeated, 1 such area / current Dungeon Level Implodes (you may choose which area(s) Implode)

AN IMPLOSION: Remove all 4 of the Dead-End dice from the dungeon, thereby leaving a large 'gap'. This new empty area might become explorable at some point!