- Instinct: reveals the location of all monsters that are equal or lower-level than yourself.
- Veteran: gain 1 addition XP from every monster killed, requires less XP to level-up
- Pit Dog: begins with 1 layer of death protection
The fighter levels up significantly faster than other classes, which has two huge benefits. Being a higher level he is more powerful and dangerous, but it also benefits more often from the full-heal and mana-restore you gain when you level up. This extra leeway in terms of experience gain and leveling up makes the Fighter a competitive class. His other class features are largely inconsequential. Pit Dog is a one-time event, and basically equivalent to one use of the CYDSTEPP glyph. Instinct is completely useless, since fighters want to avoid fighting monsters that are equal or lower level than themselves if at all possible, saving them for level-up catapults later in the game.
Although he's presented as a Fighter, this character is actually equally well-suited to being a spellcaster. He has no class features that help his melee combat skills, and largely comes across as a tabula rasa that can be played any way you want. It's always a good idea to keep an open mind with the fighter and be as flexible as possible based on what items and glyphs you find. Because of this, the Fighter works well with any race, though Goblin Fighters have a nice synergy with goblin's extra XP and the fighter's lowered XP requirements to level up.
This is the first class you are presented with when you begin Desktop Dungeons, and he functions very well as a beginner class, and also presents a strong foil to the specialized classes such as Warlord and Assassin that are unlocked later.