Brave Knight Acheron

If you have 4 or more Maintenance counters, you
may pay {u}{r} instead of its normal mana cost.
Haste, menace
{1}{u}, {t}: Tap target creature or artifact you
don't control.
{r}, {ut}: Deal 1 damage to all creatures you don't control.
The devastation wrought by Knights-Acheron
is terrifying to behold.