Every Crime Spree loud modifier as mutator.
These mutators do not reduce XP or cash. They also do not disable achievements and level completions will accumulate. They also make your game harder, so watch out.

You can find these new mutators in the "Crime Spree" tab in Mutators section

Mutators:
Assault Extender
Cloaker Arrest
Cloaker Smoke
Cloaker Tear Gas
Dozer Explosion Immunity
Dozer Rage
Heal when Medic is dead
Heavy SWAT Units
Medic Dozer
Medic Heal Speed Boost
Medic Rage
Medic Revive Damage Boost
Minigun Dozer
More Dozers
More Medics
No Animation Hurts
Shield Reflect
Skulldozer
Taser Overcharge
Winters' Shields
Zeal Snipers

For updates you need SuperBLT or BLT+.

Please submit issues/crashes/new features here