Corridor 7: Alien Invasion

The Good
This was released shortly after 'Doom' (the advertising slogan being 'Prepare to meet thy Doom', with 'meet' crossed out and replaced with 'beat'), and was hyped as a serious competitor. However, it's based around the 'Wolfenstein' engine, and despite its historical status as an early example of engine-sharing (unless you count 'Manic Miner' and 'Jet Set Willy' of course) it's not actually very good.

The Bad
Pretty much everything that is wrong with 'Wolfenstein' is wrong with this, except that whereas 'Wolfenstein' is acceptable as a historical document, this isn't. Therefore, the gameplay is extremely monotonous, the graphics are chunky and unattractive, and you just run around shooting things over and over again. The sci-fi setting should help, but doesn't, as everything looks goofy. It's basically a sub-standard shareware game granted a commercial release.

The Bottom Line
A poor early 'Doom' competitor based around the 'Wolfenstein' engine. Not good.