Payday: The Heist

A Bulldozer is a heavily armored enemy with a big suit with a glass covering the face. The armor looks like a space suit. They spawn on all heists. On higher difficulties the Bulldozer spawns more often than on lower difficulties.

You have to choose the shotgun during the load-out screen before the heist starts. There are two shotguns that you can get in the game, which are the 'Locomotive 12 G' and 'Reinbeck'. The Locomotive is unlocked on reputation 7 of the Sharpshooter tree. You will get Reinbeck when unlocking reputation 13 of the Support tree.

You have to kill the Bulldozer with either the Locomotive or Reinbeck. You only need to deal the killing shot. Aim for the head since it's their weak point. You can use another weapon to destroy the visor and then switch over to the shotgun to kill the Bulldozer but it's probably faster if you only use the shotgun at close range.

This trophy is probably easiest to do on First World Bank heist, playing single-player on easy and without AI to avoid someone else killing the Bulldozer. However there are few Bulldozer spawns and sometimes none on lower difficulties.