Teleporting drains his super faster. At range keeping him blinking will run him down. Close range shotguns work best. The Chaperone really shines here since it's got a better range if you go for the head. You biggest issue is going to be if he has transcendence. It basically doubles his time in Stormcaller at the cost of his grenades and melee. Note that means that a Warlock using it might be willing to die to avoid punching something If they think they are getting their super soon. Same with grenades.