Games like Gamma Bros

"Platypus is a sci-fi shooter game with great mechanics, sensational visuals, and excellent music. The game features local multi-player options for up to 2 players in a split screen format, as well as single-player mode. The story revolves around the invasion of the neighboring country of Mungola by the industry-laden Collosatropolis, with the latter expecting little resistance."

"Bit Blaster XL" is a fast-paced, arcade-style score-chaser game where you control a ship that cannot stop moving. Avoid crashing into enemies by turning left and right, and use boost/brake to navigate through an ever-increasing amount of obstacles. Collect ammo and power-ups to survive longer and beat your high score. The game features simple mechanics, re-playability, and extra ships to unlock.

Zombieville USA 3D is an action-packed roguelite shooter where players scavenge weapons and unlock perks to survive waves of zombies. Featuring 39 unique weapons, 28 customizable perks, and randomly generated gear, each run offers unpredictable challenges. Play solo or with friends in this intense, endlessly scaling battle against the undead.

"Jet Gunner" is a fast-paced, side-scrolling shooter game that features intense action and vintage graphics. As a mercenary named Sinclair, players must navigate through various levels while battling against hordes of enemies and powerful bosses. With a wide range of weapons and special abilities, players can customize their playstyle and strategize to overcome challenges. The game also includes local co-op mode for up to 4 players.

"Enemy Mind" is a side-scrolling space shooter for PC with a classic 8-bit art style and 8 levels of challenge across 70 waves. As a being of pure psychic energy, you can take over and control any of the 20+ unique ships you encounter, each with their own power and ability. The game features an adaptive story system that changes with your play style and offers multi-player co-op for up to four players. The soundtrack is an original chiptune-inspired creation by Rainbow Kitten.

"Blaster Master Zero is a 8-bit style sci-fi shooter game, reminiscent of the NES era. It's a single-player or two-player co-op action-adventure game, featuring new areas, bosses, and gameplay elements compared to the original 1988 game. With improved battle mechanics, a more robust scenario, and expanded exploration, Blaster Master Zero offers a refreshed take on the classic game."

"Super Galaxy Squadron EX Turbo" is a shoot 'em up game with retro-style pixel graphics and intense action. Players pilot spacecraft through levels of enemy forces, upgrading their ships and abilities as they go. The game features a variety of playable ships, numerous enemies and bosses, and a challenge mode for experienced pilots.

"Sky Force Anniversary" is a vertical scrolling shoot'em up game with modernized graphics and intense battles. The game features various aircrafts to upgrade, numerous enemies and bosses to defeat, and challenging missions with increasing difficulty levels. With its vibrant visuals and captivating gameplay, Sky Force Anniversary offers a thrilling shoot'em up experience.

"R-Type Final 2" is the latest installment in the classic shoot-'em-up series, now available on PC. The game offers updated visuals and gameplay features, while retaining the intense action and variety of weaponry that defined the originals. Confront an ever-evolving enemy in the form of the Bydo, with stages that transform and corrupted by their presence. A must-play for fans of the genre, new and old.

"Asteroid Bounty Hunter" is a space shooter centered around the veteran hero John and his AI spaceship. The game features unique boss fights, defense of nearby planets from asteroids, and battles against other bounty hunters. The concept revolves around farming experience for upgrades and collecting mastery points from rival ships. — NO RELEASE DATE OR DEVELOPER/PUBLISHER MENTIONED.