Opal Palace - Commander Anthology Volume II - 259

Land

{T}: Add {C}.
{1}, {T}: Add one mana of any color in your commander's color identity. If you spend this mana to cast your commander, it enters with a number of additional +1/+1 counters on it equal to the number of times it's been cast from the command zone this game.

Common · Commander Anthology Volume II · #259 (CM2)

Illustrated by Andreas Rocha