Pixel Dungeon

(After winning all classes in all challenges, this tierlist takes challenges into account, as well as 0 challenge play!)

S-Tier

Rogue. Best character for both beginners and advanced players, get-out-of-jail card in invisibility can be used for everything, from evading champions, evading ranged enemies, taking a breather, even getting free invis potion on piranha rooms. Assassin and freerunner are both good, but the latter is a bit better for evade-tanking and kiting in 9 challenge. Smoke bomb is the best crown upgrade by a long shot, the blink and crowd control gives so much momentum. Death mark is awful dealing only 25% damage and lasting 5 turns, and cannot kill enemies. Shadow clone is too frail and useless especially with no-armor challenge. In general minion builds should be avoided in this game, due to the high opportunity costs putting players in a worse position.

Cleric. It's too early to say, but after testing, the recent buffs made it very easy for cleric to win in high challenges, as it patched the cleric's only weakness of being weak without tome charges. Some notable skills are cleanse which gets rid of poison, burn, bleed etc. Scroll duping to get more tome charges among other things. Hallowed ground giving crowd control. High shields in ascended form, bless, hallowed, and the future paladin. Cleric has everything for any situation, from tanking to damage to movement control. Ascended's tome charge usage is irrelevant if you have scrolls, and the cleric can keep firing spells that are highly effective against demon halls enemies. On paper, the other crown upgrades are inferior compared to ascended form. While 9 challenge is still difficult, these S-rank characters have the most consistent wins, though cleric has some early-game difficulties.

A-Tier

(There's little difference between A and S, these characters are still good)

Mage. While early game is a bit difficult compared to rogue, once you get tengu's mask the cannibal grandpa starts to shine with soul eater. He's the only character that can comfortably live in the dungeon on high challenges and without items like RoW. High-rank wands like fireblast and lightning are worth slotting into the staff, but avoid the weaker ones. Use warlock, battlemage is an inferior choice due to the staff's low base power, and that the melee effects aren't impactful enough to justify using it over warlock. For crown upgrades, beacon is good for movement (but avoid telefrag at all costs as it actively kills you, it's NOT an upgrade). If I have lightning or frost, I'll take element burst over beacon due to the AoE damage + crowd control. Wild magic is the least useful and requires specific builds and unupgraded wands, but it's not as horrible as death mark etc.

Hunter. Would be almost as good as rogue, if it weren't for the fact that barren lands eliminates most of her warden kit. The fact that she's still A-tier is proof that her kit and bow is strong. Unfortunately she requires RNG to perform well, such as vampiric or sharpshooting, making her require a lot more resets. For crown upgrades, nature power is the best pick as it saves turns by moving fast and dealing more damage, it has more DPS and duration compared to death mark and can kill multiple enemies, with only a +10% cost compared to death mark. Spectral blades is inferior but still usable depending on your melee. Spirit hawk vision is redundant with the huntress's vision perks, and it's too weak and frail for combat and dart usage. The guaranteed evasion skill lets it survive better, but at best it's a small distraction before it dies. Not worth the opportunity cost over nature power!

B-Tier

Duelist. Bad early game, with FIMA and her having so many close-ranged skills she cannot use most of her weapon abilities. But gets better once you find the right weapons such as shields, spear, dagger etc. Champion needs specific weapons to work and it's an unreliable pick. Monk however has every ability you need from chasm kills, healing, parrying eye beams. Pick "challenge" for her crown upgrades, freezing most enemies is great and she heals afterwards. Elemental strike is a much worse option compared to challenge, don't pick it except if you have a shocking weapon. Feint is the worst movement ability in the entire game with high cost and poor movement, it's not worth it and you can just use challenge to reposition.

D-Tier

Warrior. The butt of jokes in high-level play, comparing him to S-tiers is like comparing Meta Knight to Ganondorf in Smash Brawl! The difference is huge, and yet again he gets completely outclassed by new heroes. You can still win with Ganondorf but that doesn't make him good, we can't compare him in a vacuum. He's the worst tank in practice; he doesn't have heals like mage and duelist, he doesn't have dodge like rogue, he doesn't have parry charges to keep like duelist, he doesn't have big shields like cleric and mage. His effective HP is the lowest in the game and he's the frailest character, and yet his kit encourages tanking for some reason. Unlike the above characters he needs Pharma, Barren, and FIMA turned off to heal. With FIMA his entire kit and armor seal is destroyed, and the few ways to play him is with kiting + movement or vampiric, which other classes can do better. Berserker is awful as it requires you to take hits and die, and warrior has no heals to offset this. Gladiator is better, but with decaying combo and poor skills it's just a worse monk. He doesn't have more armor compared to other characters, except very specific circumstances like waiting which kills. The only crown upgrade worth getting is leap, which is a cheaper smoke bomb. Shockwave is a passable crowd control when upgraded, but endure is the worst crown upgrade in the game. Very expensive charge, for 50% damage cut for 3 turns, and whatever HP you've lost is not worth the extra damage. It doesn't even null damage like duelist's skills, the opportunity cost is extreme. Additionally, he's one of the hardest character to use for newbies as they don't understand armor seal. Rogue's button tap is friendlier and more useful.

(These are usually my best picks for the highest winrate with many challenges! Taking the weaker options consistently decreases my winrate, whereas the powerful stuff increases it. Challenges in this game are horrible compared to other games and roguelikes, because Barren, Pharma, and FIMA removes entire builds like warden, warrior. That's not fun and they really need to be tweaked.)