Here's a mixtile set I made for gen V OU/UU.
Leaf Storm-STAB, pretty powerful move.
Hidden power [fire]-deals with genesect, ferrothorn, scizor, or foretress. It serves to deal with bugs that have the advantage over him, or Steel types that try to shut him out.
Rock slide-Covers 4 weaknesses in one move.
Dragon Claw-Deals with Kingdra, a pretty common check to sceptile.
For generation V, you can also use the move Acrobatics combined with a flight gem. Since the gem goes away before the game checks for items, the damage will be tripled, which, combined with Sceptile's new unburden ability, is pretty devastating.