This game's super well done! I ordered the physical copy of the game for my bro (since he started collecting NES games to play), so I'm playing the ROM file that came with the receipt in the meantime. I'm seriously blown away by how good this game looks considering the NES's hardware, so props to everyone who worked on this! This definitely seems like it would be much more fun in multiplayer, which I haven't tried yet, but it's totally fine in single-player.
Oh by the way Mac gang, yes you can play this. The ROM works beautifully with OpenEmu, which is built specifically for Mac computers. You're welcome in advance!