Shattered Pixel Dungeon

The greatest thing about the game, as well as what it taught me to love about the genre, is that there is no meta-progression that makes your in-game characters stronger.

Probably one of the most accessible traditional roguelikes, in terms of learning curve and visuals.

There is a lot of content, from classes/subclasses you can play, to equipments and consumables, to enemies and traps, etc.

Many, many different weapons, artifacts, rings, potions, scrolls, wands, seeds, enchantments, curses, traps, general useful tools and items;

The graphics are fine and the enemies are varied and mostly interesting.

You can easily play this either from your keyboard alone, your mouse alone, or even both at the same time ( It even has partial controller support.. ).