Syr Humberto, Stormbreaker

Whenever a soucer is going to cause damage you
can discard a card, if you do that, Syr Humberto,
Stormbreaker deals the same amount of damage
to the controller from that soucer.This damage
cannot be prevented and this ability cannot be
countered.
{2}{r},{t}: If a source would do damage until its
next turn, instead it does twice as much damage
"The last thing they will hear is the sound of the thunder"