You will be delighted to learn that (Advanced) Fighting in Tunnels only has four character classes:
Tunnel Fighter - doughty tunnel warrior and expert at killing things in tunnels
Maze Mage - a magic-user, skilled in subterranean magic and bending the tunnel environment to their will!
The Sapper - Engineer, scout, medic, hero!
Prospect - roll a character with less than optimal stats, and not qualify for the main classes? Reach level 2 (if you dare) as a Prospect and choose any class (even if your stats are below those normally required) and get a boost to your prime statistic.