This merc is all about confusing the hell out of the enemy:
Two active abilities.
Active: Disguise as whoever character he targets. This will only change the looks of the merc and does nothing to team-indication (still appear hostile to opponents).
Active: Feign death. Player appears to die until he choses to get back up again.
Passive: Whenever the merc is killed, a timer will start counting and after say, 10 seconds, the merc will stand up again. Always. The only way to prevent this from happening is to tap out (suicide), be gibbed by opponents or revived by medics.
What does this all mean? We end up with a merc that appears as any other merc, can bluff and make players make the wrong deciscions. It’s a very ‘slippery’ merc who’s able to make the opponent team incredibly paranoid about gibbing the opposition (because they can’t determine which player is able to stand up again by looks alone).
Combined you’ve got a player who can ‘act’ his way to the objective, have multiple opportunities to stand back up at the most unfortunate moments for the opponent and overall compell the opponent players to sink more effort into checking who’s alive and who isn’t.