Fire Bird Keeper, possibly rank 5 summoning support?

[I Hate Snatch Steal]

 

If this card is summoned: You can discard 1 card; all face-up monsters you currently control gain 1 Level, until the End Phase. You can only use this effect of "Firebird Keeper" once per turn. An Xyz Monster that was Summoned using this card as Xyz Material gains this effect.
*When it is Xyz Summoned: it gains 500 ATK and 1 monster your opponent controls loses 1000 ATK, until the End Phase.

 

Some rulings for the effect the xyz monster gains can be found here:

http://yugioh.wikia.com/wiki/Card_Rulings:Number_C39:_Utopia_Ray