I.D.P.D.

The I.D.P.D. (Inter-Dimensional Police Department) is a group of enemies set on killing the player when they reach a certain level of power.

Gameplay-wise, they are designed to be the equivalent of the player, but using tech to augment their abilities rather than mutations. All I.D.P.D. troops can damage enemies that aren't in the I.D.P.D. and can be damaged by their projectiles and Fire Traps like the player would. When your character doesn't move/shoot and the I.D.P.D. units don't get hurt, they won't attack you like all other enemies would. Details of each unit can be seen on their individual pages.

Trivia

 * The I.D.P.D's home dimension is the only reality where the apocalypse did not occur. This is why they do not drop any radiation on death.
 * JW has discussed their intent as being a preemptive strike to kill the player before they pose a threat to their dimension.
 * The I.D.P.D. speak a language that the mutants don't understand.