Metroid Prime Hunters: First Hunt, supports wireless, multi-card, LAN play for up to 4 players. This means that up to 4 people can connect to a single game, but each person must have their own Game Card (which was included with the first batch of Nintendo DS hardware units).
All the multiplayer options are available from the Multiplayer menu.
There are three different maps available for use during multiplayer play: Ancient Vestige, Trooper Module, and Assault Cradle.