Magelord seems like an awful PrC though...Spell Mastery is a truly pointless feat in most games (and I suspect it almost encourages DMs to steal the PC's spellbook, just so the feat gets some use...), and the PrC seems determined to turn the character into a sorcerer with some sneak attack thrown in on the side.
Uncanny Forethought, Exemplars of Evil, page 26. A useful reason to have Spell Mastery.
Granted, the feat and the prestige class are kind of stepping on each other's toes all over the place, but...
Yeah, that feat is pretty much all kinds of broken.
For example, if summoning is a signature spell, it only takes a standard action to use it.
UNCANNY FORETHOUGHT feat
As a standard action, you can use one of the "uncanny forethought" slots to cast a Spell Masteryed spell that could have been prepared.
Alone, that's kinda nice. The second part is even better.
As a full-round action, you can use a "uncanny forethought" slot to cast
any spell you know (subject to level limits). Your CL drops by two for spells cast in that way, but...