At the start, as in other games of this genre, you have to create and customize your character, choosing from among various races (elf, human, dwarf, orc, troll, etc.) and classes (warrior, mage, priest, thief, explorer, etc.). You can also randomize your character, or customize it down to the smallest detail.
Once you have your character set up, you can start fulfilling the prophecy that serves as the backdrop for the game's story: a hero will rise from among the rest to end the darkness that looms over Ancardia. It won't be easy to succeed in this enterprise, though.
Following the traditions of roguelike games, Ancient Domains of Mystery has an interface controlled by the keyboard only (you should read the manual before playing), permanent death, random and fatal dungeons, and very simple graphics that will take veteran roguelike players back to the good old days.
Ancient Domains of Mystery (ADOM) is a highly entertaining RPG that has more to it than most modern commercial games. Its main drawback (or asset, depending on your point of view) is that it takes time to master the controls and all the options they offer.