Each player has both a role and a character class.
The four unique roles in the game each provide vital info to the party.
The Cartographer shows the dungeon map/layout to each member of the party in the same room as The Cartographer.
The Treasurer shows each players inventory as long as they are in the same room as The Treasurer.
The Vitalist shows the players health if they are in the same room as The Vitalist.
The Loremaster shows what the items are in the room The Loremaster is in.
The roles are randomly distributed to all the players.
If you play with two people then it is possible that one player on gets one role, and that the other player gets 3 roles. It is randomized, but every player is guarenteed to get at least one role. (Actually what happens)
If you play alone you gain all four of the roles. If you play with two players, you both get two of the roles. If you play with three players, then two players get one role and the third gets two roles. If you play with four players, then all four of the roles are given to each of the players (Would be the best situation, But this is not what happens)