Reserves: Choose one: Gain 1 Force. Play only during your build step. Or: One of your opponent's units gets -2 power and Backfire 1 when attacking one of your Sith Lords until end of turn.
Keywords
Backfire
Backfire X: A cumulative ability triggered by the initial dice roll that means, "When you roll at least one natural three with this unit's attack dice before re-roll, this unit does X dice of damage to itself when the attack ends." Backfire applies only to dice rolled for an attack, not to dice rolls for abilities like Retaliate.
Reserves
Reserves: [Ability]: A layered, static ability that means, "The following ability works while, and only while, it's in the build zone." The granted ability remains to be the ability of its type. (For example, activated abilities granted by Reserves may be disrupted.)