Like every other monster, it has a big slow attack and a pause. Bait it into doing an attack, like the rear up and smash, and when its done, stab it and repeat. But its much easier to just shoot them.
My issue with them is the constant rampaging. I set up shop in a beautiful area and they have flattened every rock, shrub, and tree in a 2 mile radius. Some of the beauty is lost, though I can replant a few trees I dunno if its worth the bother, first GD that spawns will have them flatten it again. Its not all bad. If a lox aggro on me and I don't want to deal with it, I can always find a dwarf and run past it. The lox gets distracted and forgets I exist, and I get free GD loot later.

I liked them better when they were neutral, and only attacked if you got in their face. The new aggressive behavior is more annoying than challenging.