Ok, let's say I have a Warp Lightning Cannon attached to the Night Runner. I declare it has an attacker so now it gets the boost of 3 power from the cannon. During the action window that follows, can I corrupt the unit to have it deal 4 indirect damage to the opponent? Corruption states that a unit cannot be declared as an attacker but it has already been declared. So does this mean it will also deal its 4 damage in combat? How would the timing work for this? Kind of seems powerful if it works how I want it to.