There are six distinct main classes in the Kingdom of Loathing, as well as other special classes. Each centers around one of three main stats, and each has a different set of skills to use.
- Seal Clubber - Seal Clubbers hail from the frigid Northlands, because one character class always hails from the frigid Northlands. They rely on their Muscle to survive.
- Turtle Tamer - The Turtle Tamer's mystical connection with his/her terrapin brethren imbues him/her with great power. (S)he excels at moving very slowly and winning footraces with smug satisfaction. His/her Muscle is the key to his/her success, and to his/her long lifespan.
- Pastamancer - With his/her mastery of the arcane secrets of Noodlecraft, the Pastamancer is a force to be reckoned with. (S)he relies on his/her Mysticality to get ahead in the world.
- Sauceror - Long engaged in an uneasy truce with the Pastamancers, the guild of Saucerors protects the secrets of the Ancient Brotherhood of Gravymakers. Their Mysticality is their most important attribute.
- Disco Bandit - The Disco Bandit boogies to and fro, hither and yon. Whence comes (s)he? No man knows. Whither strikes (s)he next? All men live in fear of him/her and his/her Moxie.
- Accordion Thief - The scourge of mariachis and polka bands, the Accordion Thieves have plied their malign craft since time out of mind. Their Moxie serves them well in both their adventures and their interactions with "the ladies/gentlemen."
Challenge Run Classes
- Avatar of Boris - A special Muscle-based class available only during an Avatar of Boris run. Unlike the six main classes, Avatars of Boris must follow a set of very specific rules, which includes using no familiars, no permed skills, only fight with their Trusty axe, and a much lower alcohol tolerance. In exchange, they are given a bard in place of their familiar, a higher stomach capacity, and 3 distinct skill trees with 10 skills each.
- Zombie Master - A special Muscle-based class available only during a Zombie Slayer run. The Zombie Master also gets no permed skills, can use only certain familiars, can eat only brains, and has a very low alcohol tolerance. They have three distinct skill trees with 10 skills each and their skills use their zombie horde instead of MP.
- Avatar of Jarlsberg - A special Mysticality-based class available only during an Avatar of Jarlsberg run. The restrictions are similar to those of an Avatar of Boris: no permed skills or familiars can be used. In addition, they cannot use normal attacks, and their maximum Fullness and Drunkenness are reduced by 5 in comparison to a normal class. Lastly, they cannot consume regular food and booze, but can gain skills that lets them summon and process special food in their Cosmic Kitchen.
- Astral Spirit - When you ascend, you become the character class Astral Spirit, which means nothing more than lack of one of the six character classes. As an Astral Spirit, your level, Muscle, Mysticality, Moxie, HP, MP, and adventures are set to infinity, but as you might expect, on a plane of existence where everyone is the same, infinite stats are not very useful.