This is a 40 year old game and it still holds up.
A prime example of how graphics have nothing (or almost nothing) to do with fun and addictive gameplay.
The game has enough depth to keep you entertained for hours and it also comes with a manual to give you that old school feel of having to check the game's manual if you get stuck somewhere.
Its also very interesting to see the ways in which this game inspired and spawned hundreds of roguelikes, all the elements you see here are present in those other hundreds of games.

All in all its just a very fun, interesting and engaging game that I personally believe every roguelike fan should experience at least once.