Being a fan of Starcraft some years now, we decided to recreate the game on Nitendo Ds. Our team (commonly called the "StarDev") consists of the time for 2 people, me included.
I don't have a wii u anymore to test it myself, but if homebrews are not visible on the wii u menu I think you can press L + R + minus to open the plugin menu, there should be an option called "homebrews on wii u menu" or something similar
Or when your player dies, you can say in code, if enemy exists, do nothing, but if enemy does not exist, then create enemy at certain spot. (This would be a pain tho for lots of emeies)