Just run a chill clip fushion. It works as a overload and unstop weapon. Slow (on first shot) should overload (have not tried it). Freeze shatter (second shot freezes) will unstop a champ. I know for a fact this one works. Still even if the overload part doesnt work its still a unstop option. It even counters barrier champ. Keep freezing them so they can put up a barrier. Riptide from crucible(you can focus it) has a fast enough firerate and decent reload to keep the freeze chain up.