grindfest games?

Grind fest? You'll love MapleStory. Heh.

...you want a grinding game?

Runescape. No game touches it for grinding.

I wasn't aware that there were people who used "grindfest" as a positive term. Or that it wasused to advertise games...

Guess I learned something new.

I suppose you could say that Dungeons of Dredmor and FTL are grindfests. They don't move toward a long-term level like Disgaea and ZHP Unlosing Ranger, but you grind over and over again, endlessly, in a way that is VERY fun, just like those games.

Go for Paragon 100 in D3. :P

Mabinogi is pretty good an on Steam currently. It has a combat system similar to Paper Mario, the ability to play as a literal child and kill bears, free reign to build your character anyway you want, lots of crafting, randomly generated dungeons, huge world, and apparently the community is very nice. It's an MMO and they manage to keep most of the real life purchases to cosmetics or other superficial stuff.

just play through each and every version of pokemon that was ever released.

Cladun X2

Torchlight 1 - infinite dungeon after completing the main story.

But you probably already know this ;)

Dungeon Defenders needs a lot of grind and is fun/interesting. Unlosing Ranger is awesome though, loved playing through it.