Gas Mask

Effects

 * Moves Isaac to a parallel dimension.
 * Item charge starts to decrease until it is over, moving Isaac back to original dimension.
 * Darkens rooms and replaces enemies with Aberrants.

Synergies

 * Car Battery: Charge duration is doubled.

Trivia

 * The music replaced by Gas Mask is called 'Whispering Wraiths', an unused sound in the game.