I don't think I know enough games to say which one is the worst. The worst game I've played to completion is probably Sonic Forces, but I don't play many bad games, even less so to completion, and I wouldn't say it's much less than mediocre. Off the top of my head Sonic 06 and Bubsy 3D come to mind, you don't even really need to play them to see how they're so bad, but I'm sure there's much worse.
what do you mean doesn't function? like that it's riddled with glitches or that it just isn't playable? because if it's the latter then does that even count as a video game?
It was meant to be a port of this C64 game where you fly around labyrinth stages, as a bird. A game comparable to Cybernoid or, the more well known NES title Solar Jetman would also be a good comparison except, without that games asteroid controls
Anyways, That's what it was supposed to be. and here's the port:
But, the port doesn't use any of the original graphics, it doesn't even feel like the same game, and worst of all, the code is all a lie
The game was programmed with Caps lock on in an engine for ZX spectrum known as laser basic. But the game can't run with caps lock on. Meaning none of the buttons work, you can even move, once you're placed in the level, it's completely functionless.
The only way to make the game even slightly work is to actually fire up Laser Basic and use it's code editor to fix the game for the devs(yes they actually illegally left the program they used to make the game, on this casset)
And by fixing the caps lock thing, to make it so you can actually move, you'll realize the game has no collision detection. The enemies will instantly collide with you if you are within the same column of space as them (yes, it's impossible to dodge them) so the only option is to shoot your laser at them (which is of course, invisible) so that you can get through. If you shoot through the enemies and exit the room on the left there is one more screen to view with a poorly drawn apple on it. But play for too long past these screens and the game seems to crash anyways O_O
in 2018 someone made a really solid port of the C64 game to ZX Spectrum and it's so great. The original game though, just laughable I definitely think it's a great contender for worst game. Even if the poor teen who programmed it was stressed out and that's why the end product was so bad