BlitzKeep is a really neat iOS RPG where you fling yourself around on enemies to kill them in order to level up, collect power-ups and get strong enough to kill stronger enemies to repeat this cycle. You get gold for doing so, and you can use that gold to unlock new character classes with various abilities and upgrade your stats as well. I liked it and I wish I could've played it more, but after a very short while it just... stops. And the endless mode they've included doesn't do it at all for me.
The core mechanic is quite simple, you have a level - the sum of your base level and your equipment - and enemies have levels. You can only defeat them with a single bump if you're higher level than them, otherwise they kill you if you attempt this, gracefully indicated by a skull over their heads. You can give yourself a bit of a dash and temporarily increase your level as well. I'm a bit confused with the progression, you seem to keep your base level from the previous level going forward, but would that mean that you might reduce your chances of moving forward easily if you barely beat the previous level? Is there a way to override this starting base level? I kinda wish you would just start from level one every time. Otherwise, you flick your character around, finding items, unleashing spells and killing enemies. Hurry up, because you can't stay in each room forever!
Classes have various powers, my favorites being higher-level projectiles that you automatically shoot around, killing stuff without needing you to bump into them, this helps greatly for bosses too! Otherwise, some bosses are pretty dumb, they kill you almost certainly - except if you're dashing or if you're using projectiles - and some move the spots you can stand on in patterns that make it so you'll have troubles moving around, and die. After you're done with the few levels, there's an endless mode you can try your hand on, as advertised, it's a bunch of rooms one after another for you to keep playing... But you can't win gold at all there. It makes it pointless in the grand scheme of the progression.
I liked BlitzKeep, but there's too little of it. After a very small number of levels you're just greeted by an NPC claiming that there will be more stuff after a bridge someday, that's too bad because I wanted to continue fighting, unlocking classes and boosts and bump into monsters over and over right now.