Well I'm more bemused that GF didn't really give Diancie any good Physical moves at all to support Diamond Storm. It does get EP now though which certainly is nice.Moonblast works and with minimal investment even zapdos crumbles to D Storm. It honestly doesn't need it.
Someone weigh in, how does...
~ Calm Mind
~ Reflect
~ Moonblast
~ EarthPower
...hold up?
~ Rock Polish
~ Diamond Storm
~ Moon Blast
~ Earth Power
Also seems interesting, although 110 is already a really good speed tier.
If this thing got Wish it would be a pretty damn good cleric...
~ Heal Bell
~ Wish
~ MoonBlast
~ Toxic/ Stealth Rocks/ EarthPower