jackernaut - A jackernaut is someone who doesn’t get hurt easy. They can

A jackernaut is someone who doesn’t get hurt easy. They can take a lot of damage and still be a pain in the ass.

"I got hit by a rocket and still killed me. I’m a jackernaut.", @RocketMan

"He got shot 10 times and still ran me over. That’s a jackernaut.", @BulletMan

"I took 5 grenades and still kicked my ass. I’m a jackernaut.", @GrenadeNoob