Normally we use the made-up term 'Diablolike' to mean a game in the vein of hacky-slashy dungeon-crawling, but in this instance I use it to mean 'a game that really, really wants to look like Diablo III.' From colour palette to fonts, the look of Dungeon King is to my mind as shameless as a guy wearing one of those 'dip me in chocolate and throw me to the lesbians' t-shirt, but I post it because it's quite the technically-accomplished piece for a browser/Flash game. It looks great, the essential running around and chopping up monsters stuff is fast and fluid, and it's got its compulsion loops running at maximum efficiency: you won't want to stop until... well, you won't want to stop. That's the point.
It's free to play up to a certain point, at which point it asks you to fork out $10 to unlock the rest. I've not been all the way through yet so can't attest to whether it's meaty enough to justify it, but I suspect I'd probably want more than one character type and three skills for that kind of moolah.
Also, it's up against Flash's ongoing mad prejudice towards right-mouse buttons, so skill controls are nobbled into mildly awkward alternatives. I could moan about the paucity of loot and shopping too, but, y'know, Flash, technically impressive, a good half-hour of free if derivative fun. Here you go.