mount question

[adrem]

I've got an eidolon whit mount evolution.
Can I cast spell if my eidolon do a full attack (in the same round)?
need some feats? or ride check?

[LazarX]

You use the same rules that you would with any other form of mounted combat. In this case, riding an Eidolon is no different than say riding a horse trained for war.