Uchtul should work well on second turn assuming you got first hit in, or later if you manage to keep your life above 5.
You can also use
Nistarok for a first hit, and if tht fails use
Uchtul after since your life will probably be 9 or so.
Point in case, use him to ko if your life is 6+. This way if you win you ko your opp, and if you lose, you don't get backlashed. Watch out for DR though...
As for
Uchtul w/ other clans, hes ok. However, you're better off splashing
Cortez or maybe caelus or
Dregn depending on prefferance.
Cortez is still better than him in all ways as a splash...