Improved Familiar for Fleshwarper

[TallerSpine]

My player has a gestalt half-ogre barbarian/frenzied Berserker//wizard/flesh warper. We are using the variant from Monte Cook's Arcana Evolved that gives a feat every level. There's a gentleman's agreement that the players will try out classes that are in general subpar, but made playable by being gestalt. So, no one in the party is particularly optimized, even with all of the extra feats.

Anyway, this character is all about abertations (with backstory of being a failed experiment by the Daelkyr). He wants to get a cooler familiar than his lizard, but the improved familiar options are not that cool. Quasit is currently his first choice when he takes the feat.

His familiar will become increasingly aberrant from Flesh Warper. But would it be overpowered for me to let him have a gibbering mouther or some other fun aberration as his familiar?

[DrMotives]

There's an aberration specifically called out for use with the improved familiar feat. It's the eyeball beholderkin, basically a tiny little beholder about the size of a cantaloupe. It's in Monsters of the Faerun book.

[ShurikVch]

Darkness Familiar feat (Dragon #322) allow to pick the Cloaker (http://www.d20srd.org/srd/monsters/cloaker.htm) at 14th level

[Falontani]

An idea I am fond of is presented from pathfinder, called the cancer familiar. It resides in your body then just pops out when it is needed. Then with a hippogriff you have a large, with fleshwarper huge familiar that just pops out of your body. It's terrifying to imagine.

[InterstellarPro]

My player has a gestalt half-ogre barbarian/frenzied Berserker//wizard/flesh warper. We are using the variant from Monte Cook's Arcana Evolved that gives a feat every level. There's a gentleman's agreement that the players will try out classes that are in general subpar, but made playable by being gestalt. So, no one in the party is particularly optimized, even with all of the extra feats.

Anyway, this character is all about abertations (with backstory of being a failed experiment by the Daelkyr). He wants to get a cooler familiar than his lizard, but the improved familiar options are not that cool. Quasit is currently his first choice when he takes the feat.

His familiar will become increasingly aberrant from Flesh Warper. But would it be overpowered for me to let him have a gibbering mouther or some other fun aberration as his familiar?

I believe you mean Monte Cook's Book of Experimental Might. Arcana Evolved does not have the variant you mention.

Anyway, from Flesh Warper, his familiar will become an aberration anyway. Why do you need to give him an aberration on top of that? As he gains levels, whatever familiar he has will become a freak.

[ShurikVch]

How about to revive the 3.0 Alienist (which doesn't cripple your Summon Monster list), so Familiar would get Pseudonatural template?
After all, numerous Aberrations have Far Realm-related origin...

[Nifft]

His familiar will become increasingly aberrant from Flesh Warper. But would it be overpowered for me to let him have a gibbering mouther or some other fun aberration as his familiar?

Since the Fleshwarper gives a bunch of bonus features to your familiar over its 10 levels, I'd suggest giving features of the fun aberrations (e.g. "Gibber" would be one, "Spit Acid" another) rather than opening up all monsters from all books.

That would also allow you to have a familiar which becomes a new type of aberration, like for example one with two different Eye Rays (from Beholder), a mouth made of yard-long tentacles which paralyze (from Chuul / Carrion Crawler), plus Gibbering and a Swift-action Acid Spit; or plus one Choker tentacle hand instead of a tail, or whatever.