In Act 2,Chapter 2 "Indigenous Creatures", when you first get to use the rock-worm as cover against enemies, there will be two ladders behind a group of enemies where a Troika gun is located. Note: This is where Marcus says that it looks like a staging area after you kill the enemies. After killing the enemies, get up on one of the ladders before Dom or Carmine gets up. Wait for one of them to start climbing, then get directly in their way when they give their final pull upwards. They will stand on the edge and fall down. Keep doing this and eventually Carmine will give up and just stand at the base of the ladder until you go to a different area. Note: This trick might work on different ladders.