Gjallarhorn because it is good at both add control and boss damage while being very easy to use. Sleeper is a great gun as well though. It just has no add control abilities and it isnt an easy fire and forget weapon like the ghorn. Thinking about this made me understand why Ghorn was left behind. Theyll probably bring it back in the fall DLC. Easiest way ever to get some players back. "Hey guys icebreaker and ghorn are in this DLC." And the throwing of the money begins.