Presented in the Fiend Folio, and never reprinted anywhere, these grafts all require a denizen of the Lower Planes as a donor and creator. These grafts have a drawback: Good characters need to make a DC 15 Will save every day or take 1d3 Wis damage (no big deal, easily healed with an Orb of Mental Renewal or Eternal Wand of Lesser Restoration). Non-Good characters must make a DC 15 Will save or perform an Evil act of unspecified nature (so up to the DM).
Regardless, even one Fiendish graft imposes a -6 penalty on Diplomacy checks, even if they aren't aware of the graft. Aside from these, there are no drawbacks to having a Fiendish graft unless you are the party face. These grafts are the easiest to obtain, as outlined above.
- Charming Eye: 120,000gp for an item that has a Save DC of 14… For that much cash, I could just BRIBE THEM!
- Clawed Arm: +4 Untyped bonus to Str, and a 1d6 Claw attack. Just the Str bonus is worth it, the claw attack is just gravy!
- Fast Leg: Extra speed and a nice bonus to Jump/Climb, and it's dirt-cheap.
- Fearsome Eye: No, just… no. See Invisibility is not worth 120,000gp, even when it's constantly on.
- Feathered Wings: EX Flight for 10K. I repeat, EX Flight for 10,000gp. If only the Wing Buffet was a natural attack, I'd never play a character without these.
- Fiendish Ear: Cheap, but a 5% chance of being screwed over for using it is a bit too risky for my taste.
- Fiendish Jaw: 2K for an additional natural weapon. That's an effing steal!
- Fiendish Skin: It's too expensive for a +2 bonus to AC and Darkvision. Poison sucks at this level anyway.
- Flexible Arm: A weak slam, but it's an extra natural attack anyway.
- Grappling Tentacle: 7,000gp cheaper and it deals more damage while providing a +6 bonus on Grapple checks. Forget the Flexible one even exists!
- Long Arm: YOU GET AN ADDITIONAL 5FT OF REACH! I don't want to make that text bigger, but 5K for a natural weapon that has a natural reach is ballistically good. Any melee tank should have it.
- Membranous Wings: Inferior to the feathered wings.
- Springing Leg: +35 to Jump checks is nice and all, but I like my base land speed more than that. Besides, you can get Flight at 10K.
- Stinging Tail: No one cares about the poison, but the 2d4+Str on a natural weapon is really good.
- Strong Leg: This is the single cheapest inherent bonus to Con there is. 8K for a +2 is dirt cheap.
- Trampling Leg: EVen if it were half that price I wouldn't buy this.
- Whip Tail:It's cheaper than the Stinging Tail, but you can't do anything with it. The Daze DC is too low for that price tag anyway. Oddly, I think it would be more expensive if WotC excluded the Daze effect (their logic is fucked up like that).