I am on my 7th wizard and it's a balance. I've also done every other school so I have done a lot.
Here are the may casts:
Enfeeble [Charm Chopper]
Steal Ward [Steal Ward]
Cleanse Charm [Clean Charm]
Legion Shield [Defender's Rampart]
(Jewel May Cast) Empower [Expert Empowerer]
I made this pet during my quests in Zafaria and Avalon. I thought it didn't work for some reason but then when I started Tartarus at level 90, it started going off. This was also my first wizard I made for may casts this early. I usually started making my end game (PVE support based) pets once I at least hit Polaris. I recently finished Darkmoor and one run legion shield kept casting from my pet and I believe 5 out of the 8 first rounds were free shields for Malistaire.
My question is purely answered through an observation based conclusion, although if any of you other wizards can back me up on this, that would be great! At level 90. If you had a may cast pet, did it start actually may casting once you hit 90 and nothing really before?
Also, does the pip cost for the may cast spell affect it's casting rate. I seem to get a lot more legion shield may casts appose to unicorn. Would the pip difference of unicorns 3 pip and legion shields 1 pip affect that?