Serum Tank
{3}
Artifact
Oracle Text
Whenever this artifact or another artifact enters, put a charge counter on this artifact.
{3}, {T}, Remove a charge counter from this artifact: Draw a card.
Watch Out
ETB trigger, not a cast triggerRules Note
This card's ability triggers when it enters the battlefield, not when it's cast. Effects that double ETB triggers (like Panharmonicon) work here. Countering the spell prevents the creature from entering, so the ETB won't fire.