Stealth Suit

I know this is a long shot, but with the addition of Demolition charges, this would just be so cool!

A suit which makes you undetectable unless coming within a certain distance of an enemy, or until firing a weapon (muzzle flash/sound gives you away).

There could be goggles/ocular implants that could cancel it out, and/or it could be very power-intensive and only run for a short duration