You face the other two. Every tribe is at war with every other.
Up to three players; the AI takes any seat left open.
Playing with others needs an account.
A room created with a password is private: it is not listed below, and joining it needs the password.
Ask the host for a new link. The host has to keep the room page open until everyone is in, and start the match only then.
Send the other players this link:
Private room: it is not in the list of rooms, and the others need the password you set as well as the link.
Your tribe:
This room has its own address (see the address bar). Keep the page open until the match starts.