Each of your Imperials gets +1 power when attacking a unit with less printed power.
Reserves: One of your Imperials gets +3 power for this attack.
Keywords
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.)