Choose one of your opponent's units in the Space or Ground arena. That unit gets -20 speed. Shields 1 (Each unit gets -1 power as long as it_s attacking this unit.)
Keywords
Shields
Shields X: A cumulative, static ability that means, "The attacking unit gets –X power against this unit." Shields only matters when attack dice are rolled. If you give a unit Shields after your opponent has rolled for damage, it doesn't affect the roll.