Dungeoneer is high tier with a shallow ability pool. His strengths are consistent and strong damage, due to double and triple shots, and multiple ways out of sticky situations. His weaknesses are the normal monster weaknesses, and starting without food. Cloaking Device is the key power ability. It about as good as being invincible for 5 turns - AoEs and boss attacks can still do damage, but enemies will walk away in the meantime, giving you breathing room when you reappear. And the enemy-repelling effect lasts for two turns longer than the invisibility. Ranged Shot gives the ability to apply continuous damage while invisible. Get ASAP in a survival-run; Cloaking+Ranged Shot is your main combo, strong enough to let you go toe to toe with Mini-Satans. Grappling Hook is mostly overshadowed by Cloaking Device. But its cheap energy cost means it has some uses in score or survival play, and it's the Dungeoneer's main ability in a speedrun. Its mechanics are a bit obscure; when you hook a solid object, it starts looking for places to put you immediately above the target and proceeds clockwise until it finds an open spot. So you will usually end up above or right of the hook target, even if it means hooking through the target. Also, while the ability-target display only shows walls that are in vision range, the ability has a much larger range and can hit walls almost anywhere onscreen (except the very top and bottom) as long as there's a clear shot. Arrow Turret does piddly damage. But it can also block for you while you unload Ranged Shots, and is extremely tanky. Hammer Trap is an anti-boss weapon. It's sometimes possible to drop one inside a boss before they spawn, to hit it multiple times per turn. Full Auto is a devastating ultimate attack whose chaotic effect is proportional to your remaining mana. But it also randomly throws grenades, which can randomly kill you. So I would recommend avoiding it. Finally, Rail Platform seems to be not worth using, while Telepad is dedicated speedrun tech that comes online too late to use in actual speedruns. Altogether, Dungeoneer does a reasonable Fairy imitation - Grappling Hook for mobility instead of Teleport, Cloaking to replicate the damage-avoidance of an ongoing Purify and Ranged Shot to mimic wand attacks - with the downside of being a monster and the upside of triple-shots for bonus damage.