Diancie

Regular Diancie isn't exactly useful for much; its low Attack stat makes it a pretty bad raid attacker in general. What it does offer, though, is a powerful Mega Evolution, so make sure you Mega Evolve your Diancie if you wish to leave an impact in raids with it.

It has an unreleased signature move called Diamond Storm, but its parameters would have to be incredibly absurd to make Diancie worth running as a Rock attacker in general.

Best PvE Offensive Moveset

• Rock Throw and Rock Slide is Diancie's optimal set.

• Power Gem is outclassed by Rock Slide
• Moonblast is a bad move in PvE and Diancie does not get a Fairy Fast Attack to even think about being a Fairy attacker

Rock Throw provides significantly higher damage than Tackle, but comes at a slightly smaller energy gain.

Rock Slide is Diancie's cheapest Charged Attack and benefits from STAB. Moonblast also benefits from STAB and offers coverage against Fighting-type Pokemon; it is Diancie's strongest Charged Attack. Power Gem is outclassed by Rock Slide.