nice looking game! I defiantly like the style of it. I can tell you put some work into this game :). one idea for a new monster for your sequel could be a huge guy chasing after you and all of his appendages are snakes or something along those lines, lol, just trying to help out!
"I can defy gravity and do seven somersaults in midair. I can unlaoad twelve rounds faster than you can blink. I can take a bazooka blast standing. I've shot down aliens and have wrestled mutant lizards to the ground. But water makes me explode." HE IS A ROBOT man lol
 "Nightmare Runner"){kind=icon}
 "GunBot"){kind=icon}
 "UPGRADE COMPLETE!"){kind=icon}