hyper beam and rescue energy

[KentuckyFriedCombusken]

Player A uses hyper beam(Gyarados from call of legends) to knock out player B's pokemon as well as discard rescue energy.

My question is does player B get to return his pokemon to his hand via rescue energy or will hyper beam discard the energy first before KOing player B's pokemon?

 

[PokePop]

Please edit in the Pokemon's name that is using Hyper Beam.
It's best to read the card before making a ruling and I need to know the card before I can read it.

 

[PokePop]

OK, thank you.

Gyarados' player gets to choose the energy card that is discarded. All attack effects are done before a Pokemon is Knocked Out and discarded. So, since Rescue is already gone, the Pokemon would be discarded.