Shockwave, Cold Strategist

More Than Meets The Eye {1}{w}{u}{b}{r}
Whenever a legendary artifact creature you control converts or enters the battlefield, choose one that
hasn't been chosen this turn. After this ability
triggers for the fourth time, convert Shockwave.
•Put two +1/+1 counters on target artifact.
•Deal X damage to any target where X is the mana
value of the creature that triggered this ability.
•Draw a card.