Reduced Cost 5: If you have more units in the Ground arena than your opponent.
Pay 7 Force Put 3 damage counters on one of your opponent's units in the Ground arena. Play only when no unit is attacking.
Keywords
Reduced Cost
Reduced Cost X: A selective, static effect that means, "This card’s cost is X if the listed condition is met." Reduced Cost on cards refers to the build cost, except for Battle cards, where it refers to the Force activation cost. For this keyword, the conditional statement will always start with "If" for clarity. The condition must be met in order for you to be able to pay the "Reduced Cost."