Dang, nobody's replied to this guy yet? There's been a lot of updates since this first leaked.
For starters,
here's some footage. And secondly, a branch of the touchHLE emulator has been made that allows us to play Gero Blaster/StarFrog on the PC. Get it
here, but make sure to change the "preferred language" option in touchHLE_options.txt or whatever it's called to "ja", unless you manage to get your hands on that fan-made DeepL English translation .ipa file floating around the CSMC discord.
And the game itself? It's blatantly unfinished, obviously, but at it's best it's about as fun as the final Kero Blaster. You often have to backtrack through the levels after you beat them, but the first three stages are short enough where this isn't an issue. Stages 4-6 are where the backtracking gets truly irritating, with you having to trudge through long stretches of flat enemy spam multiple times in order to proceed. At least Stages 6 and 7 have a fairy at the end that just teleports you to the start.
...Wait, why didn't he just do this for all the levels?
But yeah, the Umbrella is fun to use, the Jetpack functions completely differently (you have to see it for yourself), and the weapons are still a lot of fun to blast enemies with. Though, i can see why the rocket weapons were scrapped, they're overpowered and yet not that satisfying to actually use. Several of the bosses are little more than frustrating damage sponges, but the few that aren't would've felt right at home in Kero Blaster, if perhaps a bit too simple in some instances.
Soooooo yeah, there's not all that much stopping us from experiencing Gero Blaster now. Which is still
crazy to me.