Sundark, Spell Piercer

Whenever a spell or activated ability is countered
by a source you control, you may draw a card.
Whenever mana is added to your mana pool by a
source other than a land, put X +1/+1 counters
on Sundark, Spell Piercer, where X is equal to
the amount of mana.
"Did you really expect that to work?"
— Sundark, Spell Piercer