Thievul

Thievul is one of those early-game Pokemon that can work for a while, then you put them away and never use them again. It's the same story for Pokemon Go, except you really don't want to waste your Stardust on it at all.

Best PvE Offensive Moveset

• If you really want to use Thievul, then go with Snarl and Night Slash for a STAB Dark Type moveset.
• Quick Attack and Play Rough are easy-skips.

Best PvE Defensive Moveset

• Snarl is a bit stronger post-STAB, but Quick Attack has stronger neutral coverage against Thievul's would-be counters. Neither one is going to make much of a difference, though.
• Night Slash has a chance to actually be used. Play Rough is also okay.

Snarl quickly generates energy, Night Slash has low energy requirements and a chance to boost Attack, and Play Rough has reasonable power and counter-coverage.... while also being the only other Charged Move that Thievul knows.