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Update []:
As of today, the full version of Bad Computer's shoot 'em up, Razing Core, for the Sega Master System is officially out!
As documented on its itch page, the Sega Master System game contains 7 stages to play through, upgradeable weapons, "screen-filling bosses", and a checkpoint system (and infinite continues) for beginners. That's in addition to a tremendous chiptune soundtrack from Love Penguin (formerly known as Polaria Poyon), and illustrations from Danmakuman.
The game currently costs $7.99, with an updated level 1 demo available for free to those who want to try before they buy. A physical release is also planned for next year.
Here's a short summary of the game, courtesy of the developer:
Razing Core is a vertically scrolling shoot 'em up for the SEGA Master System and Mark III console. On a routine deep-space mission the Horizon encounters an unknown object, the Core. Without warning it pulls the Horizon into its slipstream at light speed and heads for Earth.
You are about to drop out of hyperspace into a war zone. With the Horizon's firepower and the Core's unexpected aid at your disposal, you must destroy the invading alien armada to save humanity.
You can grab the game and its demo here.
Original Story []: Bad Computer has to be one of the most prolific creators in the Sega Master System homebrew community at the moment.
The developer of games like Frontier Force, Star Runner, and Blast Arena, he is regularly putting out new original titles for Sega's legendary 8-bit system, and is already hard at work on his next major title for the console: a vertically scrolling shoot 'em up entitled Razing Core that is shaping up pretty nicely, from what we can tell.
Razing Core, according to Bad Computer, was developed using his own custom engine (primarily for the "collisions, behaviour, effects, etc), with a lot of low-level assistance and tooling help from devkitSMS. It features music from chiptune composer Polaria Poyon and is designed to run on most emulators as well as real hardware.
A demo of the game was launched just a couple of days ago (Saturday, July 26th), giving players their first opportunity to get some hands-on experience with the new title, featuring a run-through of the first stage of the game (still a work in progress), alongside a short tutorial section demonstrating the three main forms of attack (Rapid Shot, Core, and Burst Charge).
As you might expect from a game of this style, the aim is for players to blast away the various enemies in their way, collecting power-ups and trying to get a high score, with the stage climaxing with a pair of boss fights against a group of large enemy ships. Admittedly, it doesn't take all that long to complete, but it is a pretty exciting taste of what's to come and features three difficulty levels if you want to go back to the very beginning and try your skills at some of the hardest settings.
You can grab the demo of the game here, if you want to give it a shot. Happy shooting!