Rule 904.2 · Archenemy
The default setup for an Archenemy game is the Team vs. Team multiplayer variant (see rule 808) involving exactly two teams. The attack multiple players option (see rule 802) and the shared team turns option (see rule 805) are used; no other multiplayer options are used.
Subrules
One of the teams consists of exactly one player, who is designated the archenemy.
The other team consists of any number of players.