ANSI graphics but hardcore puzzles
ZZT was a love project of Tim Sweeney who would later come to work as a designer and coder for UT games. However, back in the day, this was a freeware of his that was highly popular, so much so that many have added to it, modding and expanding it. You could look at it as a puzzler, but that would only tell half the story. Because ZZT is more of an interactive experience, like a top down RPG at times, other times like a puzzler and other times having a bit of an action attitude. Do give it a try, the ANSI graphics will soon grow on you, and besides, the game is very well produced design wise. Even those ANSI characters are well used, to describe shades of color, monsters, spaces and items, so, try it at least to see how much more could be sunk into ANSI graphics, which was an art in itself. Also, ZZT is a long game, so if you like it, you'll have a lot of it to return to once and again. Not a classic for nothing, ZZT truly is a high representative of RPG/Dungeon crawling/puzzle/action adventure from its time, in my opinion, for ANSI and ASCII games, a definitive must play, along with Rogue and others.