A perfect sidescroller in the Doom engine isn't possible... or is it actually? GreenLegacy proofed that with the power of GZDoom's ZScript it's not only possible but it's also very good an fun to play. Echo is GreenLegacy's first commercial game and influenced by several side-scroll-games such as Metal Slug or Megaman,  and it does very well with that. What is it about?

M16 is the protagonist of this game. He was famous butler robot. But after Mutant Armageddon started, he got the order of Dr.Miller who created M16.His mission was saving the people's life from the mutant. After adding combat capabilities to M16.He armed with plasma weapon and combat gear that never has before.Now all he needs to do is eliminate all enemies to bring peace back to the earth...

Sounds like fun? It definitely is. Check the newly released demo from the development thread and support the project!