Zebu'u - Lord of Vengeance (It's been a long time, YCM!)

[Radiant F.U.R.Y.™]

Effect:

2 Level 10 DARK Fiend-Type Monsters

This card is not destroyed as a result of battle(damage calculation is doubled). Up to twice per turn, when this card is targeted, you can activate the appropriate effect(s), according what targeted it:

Attack: Pay Life Points equal to half the ATK of the attacking monster. Banish that monster and all monsters with the same name as the banished card in your opponent's Deck and Graveyard.   

Monster Effect: Negate the activation and change that monster to face-down Defense Position. That monster's Battle Position cannot be changed while you control this face-up card.   

Spell, Trap, or Spell/Trap: Discard 1 card, negate the activation of that card(s), destroy it, and if you do; your opponent loses 1000 Life Points

[cloud7812]

I don't see how you can XYZ to get that card out. Only two cards that are Lv 10 and are Fiend is Darkness Necrosphere (http://yugioh.wikia.com/wiki/Darkness_Neosphere) and Earthbound (http://yugioh.wikia.com/wiki/Earthbound_Immortal_Ccapac_Apu)

[Flash Flyer - Sakura]

@above user: You missed a lot of them (there are other Level 10 Fiends; underlined are things you mentioned).

• Wicked Gods
• Raviel
• Ccapac Apu
• Neosphere
• Xexex [champion card]
• Steelswarm Hercules
• Supremacy Sun
• Yubel

It's a long list of monsters, but it's difficult to pull off outside of Level changing effects. Yes, Rank 10 options do exist but they're generic w/easier summoning conditions.

Aside from that, why would you double any Battle Damage you take from this card?

 

On effects, they're not too bad, but as mentioned earlier, it is difficult to summon this card given its restrictions on Materials.

I'd increase its ATK a bit so he can survive longer [and minimize the damage your LP takes, given he's doubling any pain taken; unless you have some support cards to reflect the increased damage to your opponent in mind]

[Radiant F.U.R.Y.™]

Thanks @Sakura. Ill make a couple of adjustments