Demo vmf here: http://xzzy.org/files/games/tf2/collisiontest.vmf Basically I need to filter a trigger_hurt on the front of a train, the filter entities in the vmf are set up to catch all cases except one.. the bomb properly collides with other bombs and players (and engineer buildings). It also properly opens doors. However the one exception I've been unable to solve.. the trigger_hurt always fires when it hits a func_respawnroomvisualizer. As near as I can tell filter classes can't work on this entity. Does anyone know of a solution or workaround?