An FFA (4 player) map on Lost Temple with a nice little twist to it:
After 1.5 minutes a random player is selected (without the others knowledge of who he is) to be the phantom and he is granted double income. He's goal is to be the only survivor while the others goal is to destroy the phantom.
The hard part is to find out who is the phantom and form alliance against him. But be careful you might end up back stabbed if you make the wrong decision.