I am only a 15 or so, but so far it is less a rotation, and more a priority system... Against a normal mob = leap-battering-vicious til dead (assault when needed) Against harder mobs = leap-battering-rupture-ravage-vicious (assault as needed), use rupture/battering/ravage as they come off cooldown. I am sure this changes as more skills are gained, but it's a start at least.