Blue Mana Battery

{4} · Artifact

{2}, {T}: Put a charge counter on this artifact. {T}, Remove any number of charge counters from this artifact: Add {U}, then add an additional {U} for each charge counter removed this way.

Motor: se resuelve a mano

Rulings (1)

Can be tapped even if it has no counters.
Wizards of the Coast · 2004-10-04