player A plays ES.
He resolves and gains 1 rocket counter
He activates his ability to deal one dmg
In response player B casts murder
Murder resolves first and ES is removed from the board
Yet, the missile still Hits for dmg..

I posted this in the alpha bug forum by accident sorry.
I want to know if this is how hex works as I am a mtg player and normally this chain would result in the cancel of ES' s ability

Thanks in advance.