Apeiron
Overview
Apeiron was one of Ambrosia Software's earlier games, a quirky take on Atari's Centipede. It's definitely a game that I probably wouldn't have talked about if I didn't play it in my youth...which I wasn't very good at.
Review
I'm afraid that you just don't see very many reviews of Apeiron these days. Sure, there's probably one hidden deep within some Mac magazine from the mid-1990s, but when it comes to text-based reviews of this game, you only get weird people reviewing them, like me or this fellow from Neocities who fancies himself as a "self proclaimed living doll"...but like I said, despite the manic gameplay that you could play for yourself on a Mac emulator (unless you have a real Mac that's the only way to play it), it's still Centipede's gameplay. While Apeiron unfortunately has no source port and is locked onto the Mac (the publisher, famed Mac developer Ambrosia Software, is defunct), it at least is playable in the latest build of SheepShaver, but only if you use the mouse-lock feature (most pre-2020 builds do not work due to no ADB emulation). Much like with Bubble Trouble a number of years back, my high score was miles higher and better than anything I had ever achieved on a real Mac years ago owing to being better at video games at general, and I got to see some of the crazier stunts the game begins pulling on you. The in-game help informs you that the mushrooms that litter the screen are harmless and only block your way but "grow some teeth" later on, which in this case, means they'll randomly jump off the screen at you sometimes, and later, deflect your shots. Ouch!
Player Notes
The review above is an updated and edited version of what appeared on Games of November 2020.
Port & Rerelease Notes
Apeiron did see a Mac OS X release in 2004 as Apeiron X but it didn't get Universal Binary so by the early 2010s it was just as unplayable as the original. I think that like Bubble Trouble X, it is crippleware-style shareware unlike the original which only had a screen pleading for you to buy it. You can find it for Mac here (here for Apeiron X).