Talexis' Aether Overcharger

Artifacts cost you {2}less to cast
When an Artifact enters the battlefield under
your opponent's control, Talexis' Aether
Overcharger deals 2 damage to them.
When you play an Artifact spell, put a charge
counter on Talexis' Aether Overcharge.
{2}{r}{t}: Remove 3 charge counters from
Talexis' Aether Overcharge, do 3 damage to
target creature or planeswalker.