The rules for contested unique units are as follows:
- If both players have a unique unit with the same name in battle at any time during the battle phase, the two units are contested.
- When units are contested, players bid Force to win the contest. The bidding starts with the Dark Side player, who makes his or her first Force bid (of 0 or more). Then the Light Side player makes his or her first Force bid (of 0 or more). After that, bidding continues to alternate between the two players until neither player wants to raise his or her Force bid. Players can't bid more Force than they currently have.
- When the bidding ends, each player adds his or her unit's total build cost and final Force bid. (Total build cost includes +1 for each card stacked under the unit.) The player with the higher total wins the bid. (The Dark Side wins ties.)
- The winner of the contest pays Force equal to his or her final Force bid, and his or her unit stays in battle. The losing player pays no Force, and his or her unit retreats without tapping.
- If there is more than one pair of contested units, the Dark Side player chooses which pair to bid on first.
- If you lose a contest for a unique unit, your unit retreats without tapping. You can put the unit back into its arena in your next build step. The unit will be contested again if your opponent's unit is still there.
- If a unique unit is discarded, you can build and deploy another copy of that unit. (When a unit is discarded, it's not actually "dead" -- just out of the game.)
- Unique unit cards refer to themselves by name. Unit cards that aren't unique use the phrase "this unit." But the card Nexu from the Attack of the Clones set was accidentally printed using its name, "Nexu," rather than "this unit." It is not unique, so its rules text should have used "this unit."