Dungeon Crawl Stone Soup

No elaborate plot, no dark forces threatening a kingdom – just fighting your way through a dungeon, as the title implies.

Stone Soup is a fun hack-and-slash roguelike that accepts what it is and does it well. It's not much to look at, but with 22 races and 29 classes, fairly deep systems for skills and religions... the list goes on.

Like most roguelikes, there is a steep learning curve involved, though using the 'tiles' (graphical) version helps mitigate that. It is also exceptionally brutal to new characters, though with a bit of practice (and luck), that can be overcome.

If you're after a free RPG with near infinite replayability and depth of mechanics rather than plot, Stone Soup might just be that game.