Zangband

In 1999, the Zangband dev team took the classic roguelike Angband and asked, “What if we added way more chaos?” The result is Zangband, a sprawling dungeon crawler inspired in part by the multiverse of Roger Zelazny. Expect endless procedurally generated caverns, permadeath lurking around every corner, and enough arcane systems to make your head spin. Like its parent game, it’s tough as nails, but fans swear by its depth. It’s the kind of game where you spend more time reading wikis than actually playing—but when it clicks, it’s addictive in the most old-school way possible.

“The game of Zangband is a single player computer role playing game set in the world (although 'worlds' might perhaps be more accurate) of Amber created by the author Roger Zelazny. Zangband is a variant of the game Angband which is descended from the game Moria which is in turn based upon the game Rogue (hence Zangband's classification as a roguelike game). Rogue was, perhaps, the first computer game to use the terminal screen graphically with ASCII characters representing the player, dungeon features, objects and monsters as opposed to the text adventures of its day.” - Zangband dev team