Karn, The Lonely

Defender, affinity for artifacts
Treat colored mana symbols in the mana
costs of cards you own as though they were
snow mana. {s}: Add a +1/+1 counter to a creature you control.
{s}{s}{s}{s}{s}: Remove all +1/+1 counters from creatures you control,
then deal damage to any target equal to the number of +1/+1 counters.