After solitaire and mahjong solitaire, it is only natural that Tetris will show up. Of the three of them, I would be hard pressed to guess which was most prolific. This specific Tetris clone is XTetris, which is an overall rather enjoyable version. It has a drop preview and both rotation directions, with hard drop as the drop method. No multiplayer, hold, T-spins, multi-piece preview or any modern Tetris trappings. Just a fun, basic Tetris marathon. As illustrated by the screenshots, it can be configured for either colour or black and white displays.
A non-graphical version of Tetris was originally written by Adam Marguilies, then a later SunView version of Tetris was released by Phill Everson and Martyn Shortley in March 1989. The SunView Tetris was ported to X11 by Didier Tallot and released on 29 May, 1989. Dan Greening and Janet L. Carson took over to turn it into XTetris 2 and continued development with several other contributors for few more versions.
Unfortunately, there do not appear to be any available sources for the original XTetris, so only XTetris 2 is shown here. I also haven't managed to track down the specific non-graphical version by Adam cited in the changelog.
Here is a sample session of the game. I initially started playing with an arcade stick and antimicro, but eventually ran into several cases of double drops. I switched back to the keyboard after that mess.
XTetris 2 can be downloaded from the SunSITE archive, and probably a few other places. This builds as-is on anything earlier than GCC 10. Anything newer will either require fixes or a work-around as described in this Gentoo Linux article.
In general, a quick and dirty solution is to add -fcommon to the linker options. For Imakefile, this means adding it to CCOPTIONS:
CCOPTIONS += -fcommon
I've included a patch to update this so it can be built on modern machines. This patch also enables colour by default, because why not. You should also refer to the README file for some additional steps needed in the build.
Note, however, you may run into permission problems saving scores, so that's something to look into if you care about your score. The score text in the main window is unfortunately cut-off, so you can't really see your score during normal play.
More general information on old X games, including build tips can be found in the Old X Games article.
If the above video does not work for you, it is also available on my YouTube channel.