Memfis is a cool dude that was more of a speedrunner than a mapper until 2011, when he started publishing some small levels he'd been doing, starting with VODEIM21. It's nice that he's taken less than two years to craft subsequent offerings, though it would be cool if he would pick up where he left off with the rest of Voyage to Deimos (admittedly an implausibility in his current state of mind). I say that because it's a fun if not exactly easy level to play. It's a single level for the original Doom, of course, replacing E2M1. I presume that it runs in vanilla Doom as the target port isn't listed, but I don't know that from experience, so don't quote me on that.
The most important detail about this level - besides the fact that it's purportedly Deimos-themed (though still looking a bit like Phobos) - is that it's heavily weighted toward Tyson-style play. Are you comfortable pistol-whipping (for boring / safe players) or berserking through enemy lines? Then you'll have a lot of fun here, as you don't get a shotgun until roughly halfway through the level. I can get behind playing Punchinello and the monsters are used in a manner that's not frustrating. The monster closets that open as you pace your way back through the level to the exit are varied enough to escape the Fava Beans trap of worthless surprises so that you'll have to prioritize your targets a bit, especially if you're low on health (heyo shotgun guys).
E2M1 also has some nice architecture for an opening level. The central room with the nukage is an obvious highlight; that elevated corner to the southwest reminds me of so many Link to the Past dungeons, giving you a taste of the lower area by way of the upper while separating them. There's also that winding pathway right at the entrance and probably my favorite bit, the fakeout exit. It's not exactly a trap, but... Well, you'll see it when you get to it. I'm not sure if any of the encounters here really stood out to me. Punching one imp feels about the same as punching any of the others. Actually, the telegraphed blue key trap is my favorite battle. It's a nice bit of claustrophobia in a level that is predominantly about maneuverability and exploding your enemies with rage.
Voyage to Deimos: E2M1 may replace a starting level but with all the action contained within it feels more than capable of standing on its own as a released work. Would it be great if the rest of the episode made its way to existence? Undoubtedly. Heck, he can keep up the Tyson-style gameplay through the whole thing. Classic Doomers and people looking for maps designed around punching imps into kibbles should give this level a shot.