ATK/HIT/DEF being linear make them pretty ignorable skill upgrades at later levels.
Only must haves so far have been defend and strength. Crit chance gets an honorable mention.
Stats rise linearly but the calculation that determine the final % are non-linear. They are based on the difference between you and the opponent's skill.
Storm mage and necro are the top of the heap (AoE stun and Lifesteal/infinite mana), but everybody seems pretty viable.
Rogue might need some help (or maybe I just don't understand the rogue mindset).
Yeah rogue is gonna need a big update. The original idea (which I'd like to tweak him to fit) is for him to avoid most fights with stealth, fighting only when needed using his sneak attack bonus. I want him to sneak around the whole level grabbing all the loot and leaving with minimal combat. Someone suggested lockpick as a talent so he can always open all the locked doors. I'm considering making it so that when the rogue descends a set of stairs for the first time he gains exp for all unkilled enemies on the previous level (not counting respawns) to further emphasis combat avoidance. I really want to get him to play differently than the other classes and not just be another variation on 'kill everything that moves'.
lots of areas seem unfinished (I just 100%'d the game, and there were several areas that never spawned all their items. The 100 floor tower is missing an ending, stuff like that).
Most of the fights are solved with the same combos. Food is a bit overpowered. Lane changing is almost never useful (aside from 2 boss fights). Poison is almost never useful. Bleeding is actually never useful.
Most of the items aren't worth buying at any stage in the game. Pets are almost entirely worthless.
Still, the game was fun enough for me to finish it. I'm happy in spite of my criticisms.
This game is really hard, but I like how each floor is a puzzle.
I wish the pace of the game was a little faster though, because I actually enjoy not idling this game.
New update seems to make bosses immune to everything besides air and gravity.
I know this is supposed to make the game more complicated, but all it does is reduce the number of offensive skills that are viable. Darkness builds are no longer reliable, earth stacking is no longer reliable, ice stacking is no longer reliable. The game is actually worse off for these changes.
If you want to add enemy variety, please add a wider variety of skills to compensate. As it is the game is incredibly linear in its strategies.
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Stats rise linearly but the calculation that determine the final % are non-linear. They are based on the difference between you and the opponent's skill.