A roguelike action game against evolving enemies. Wipe out the Legion across shifting battlefields, hack enemy facilities, and grow stronger with every Cartridge. Get ready for intense retro sci-fi combat!

<h2 class="bb_tag" >🎮 A New Experience in Sci-Fi Action Roguelike</h2><video class="bb_img" autoplay muted loop playsinline crossorigin="anonymous" poster="https://shared.akamai.steamstatic.com/store_item_assets/steam/apps/4021240/extras/aad17bfc43a8b37abe65dee6773d0766.poster.avif?t=1758452117" width=800 height=450 ><source src="https://shared.akamai.steamstatic.com/store_item_assets/steam/apps/4021240/extras/aad17bfc43a8b37abe65dee6773d0766.webm?t=1758452117" type="video/webm; codecs=vp9"></video>Retroid: Cartridge Protocol combines fast-paced combat, unpredictable enemies, and the thrill of progression into a high-quality sci-fi roguelike experience. Every run offers new battles and strategic choices, keeping the challenge fresh and immersive.<h2 class="bb_tag" >🚀 This is our first demo!</h2>The journey of Zero-One, the last hope against the Overmind army, begins now.As this is the first public version, there are still many rough edges.That’s why your feedback is incredibly valuable.Share your honest thoughts from battle, and help us prepare for stronger evolutions.<h2 class="bb_tag" >🛠️ What’s next</h2>We plan to launch Early Access later this year.This demo is only the beginning of that journey.With your feedback and support, we’ll expand the content and polish the gameplay—ultimately leading to the mission of finding every cartridge, unlocking your final evolution, and reclaiming the planet from the Overmind army.<h2 class="bb_tag" >📘 Lore</h2><video class="bb_img" autoplay muted loop playsinline crossorigin="anonymous" poster="https://shared.akamai.steamstatic.com/store_item_assets/steam/apps/4021240/extras/7ba28e9116476c3207c9a5097216ee58.poster.avif?t=1758452117" width=960 height=540 ><source src="https://shared.akamai.steamstatic.com/store_item_assets/steam/apps/4021240/extras/7ba28e9116476c3207c9a5097216ee58.webm?t=1758452117" type="video/webm; codecs=vp9"></video>Once overshadowed, Dr. Victor stole Dr. Evelyn’s groundbreaking technology out of envy, creating the Overmind army to seize control of the planet. As Prototype Zero-One, you are the only one who can unlock the hidden power within the cartridges and reclaim the world.<h2 class="bb_tag" >⚔️ Features</h2><ul class="bb_ul"><li>Unpredictable battles – Enemy evolutions create new combat patterns every run.</li><li>Simple yet deep controls – Outsmart foes and map traps with melee strikes and precise dashes.</li><li>Progress through exploration – Permanent and temporary upgrades fuel long-term growth.</li><li>Detailed sci-fi design – Immerse yourself in a richly crafted futuristic world.</li></ul><video class="bb_img" autoplay muted loop playsinline crossorigin="anonymous" poster="https://shared.akamai.steamstatic.com/store_item_assets/steam/apps/4021240/extras/580a29052fc7398c1d0052aa2fe08823.poster.avif?t=1758452117" width=960 height=540 ><source src="https://shared.akamai.steamstatic.com/store_item_assets/steam/apps/4021240/extras/580a29052fc7398c1d0052aa2fe08823.webm?t=1758452117" type="video/webm; codecs=vp9"></video>Find every cartridge. Unlock your final evolution. Take back the planet from the Overmind army.

Retroid: Cartridge Protocol Demo

Endless battlefields, endless threats from the Overmind army. Grow stronger through retro game cartridges, unleash powerful action, and dive into relentless roguelike combat. In this blend of classic vibes and modern impact, become the last hero to reclaim the planet.

<h2 class="bb_tag" >🎮 A New Experience in Sci-Fi Action Roguelike</h2><video class="bb_img" autoplay muted loop playsinline poster="https://shared.akamai.steamstatic.com/store_item_assets/steam/apps/3867650/extras/95efc24cc14a43f5383e080fabfdc296.poster.avif?t=1775047181" width=800 height=450 ><source src="https://shared.akamai.steamstatic.com/store_item_assets/steam/apps/3867650/extras/95efc24cc14a43f5383e080fabfdc296.webm?t=1775047181" type="video/webm; codecs=vp9"><source src="https://shared.akamai.steamstatic.com/store_item_assets/steam/apps/3867650/extras/95efc24cc14a43f5383e080fabfdc296.mp4?t=1775047181" type="video/mp4"></video>Retroid: Cartridge Protocol combines fast-paced combat, unpredictable enemies, and the thrill of progression into a high-quality sci-fi roguelike experience. Every run offers new battles and strategic choices, keeping the challenge fresh and immersive.<h2 class="bb_tag" >📘 Lore</h2><video class="bb_img" autoplay muted loop playsinline poster="https://shared.akamai.steamstatic.com/store_item_assets/steam/apps/3867650/extras/b0b3de0ac41b2cdfa19a19a256eebbcb.poster.avif?t=1775047181" width=960 height=540 ><source src="https://shared.akamai.steamstatic.com/store_item_assets/steam/apps/3867650/extras/b0b3de0ac41b2cdfa19a19a256eebbcb.webm?t=1775047181" type="video/webm; codecs=vp9"><source src="https://shared.akamai.steamstatic.com/store_item_assets/steam/apps/3867650/extras/b0b3de0ac41b2cdfa19a19a256eebbcb.mp4?t=1775047181" type="video/mp4"></video>Once overshadowed, Dr. Victor stole Dr. Evelyn’s groundbreaking technology out of envy, creating the Overmind army to seize control of the planet. As Prototype Zero-One, you are the only one who can unlock the hidden power within the cartridges and reclaim the world.<h2 class="bb_tag" >⚔️ Features</h2><ul class="bb_ul"><li>Unpredictable battles – Enemy evolutions create new combat patterns every run.</li><li>Simple yet deep controls – Outsmart foes and map traps with melee strikes and precise dashes.</li><li>Progress through exploration – Permanent and temporary upgrades fuel long-term growth.</li><li>Detailed sci-fi design – Immerse yourself in a richly crafted futuristic world.</li></ul><video class="bb_img" autoplay muted loop playsinline poster="https://shared.akamai.steamstatic.com/store_item_assets/steam/apps/3867650/extras/3ec6d6c9bd40b6b929197a8fd7fbd1fc.poster.avif?t=1775047181" width=960 height=540 ><source src="https://shared.akamai.steamstatic.com/store_item_assets/steam/apps/3867650/extras/3ec6d6c9bd40b6b929197a8fd7fbd1fc.webm?t=1775047181" type="video/webm; codecs=vp9"><source src="https://shared.akamai.steamstatic.com/store_item_assets/steam/apps/3867650/extras/3ec6d6c9bd40b6b929197a8fd7fbd1fc.mp4?t=1775047181" type="video/mp4"></video>Find every cartridge. Unlock your final evolution. Take back the planet from the Overmind army.