Total Carnage Trophy in Twisted Metal: Black
Inflict maximum damage in one attack.
How to unlock Total Carnage
You will need to pick up the SAT (same pick up as the Zoomy/Reticle). Launch it into the air and wait for the target on the ground to turn red and if it is on another car, push again to fire it. You will know if you did this by seeing the Maximum Damage notification on the screen.
This will also potentially unlock in Split Screen mode. Thanks to J2V89 for confirming.