Excellent game ! but there is bug in the game please take a look at the end of the video.

Can't play the rom on Super Retro-Cade (it runs other new NES roms). I see only solid grey screen. Any idea why?

Also, several life energy hearts can be exploited like that third key. I noticed this a lot in the 4th stage. 

Sometimes the area's load screen gets stuck. There seems to be variable load time. A few times I've just loaded a save state because it doesn't seem it will make it through. The screen for the finale stage locked up twice. I'm playing using the Mesen 0.9.9 core in RetroArch. 

Is it intentional there is no indication how many lives you have? Once I got to the 5th stage death was permanent, and I wasn't sure if that's just a function of being in the enemy's main headquarters or if I had a certain amount of lives and had lost my final one.

(Great game btw! Just reporting the bugs so you can get them out.)

I really enjoyed playing this game and I finshed all the levels! That's great that the game has a storyline, some introduction before each level with nice arts and in-game messages, it makes much more interesting to play. That music and picture creates nostalgy atmosphere. Each level in the game looks different and great designed! Here are some screenshots (please ignore emulator error, same key mapped to screesnhot and load state 9):

This game shows promise but this feels like an incomplete and buggy build. If you press start too much during the intro cutscene, the nametable and attribute table get corrupted.

I was asking a few more people in the NESDev discord and they reported similar problems in other emulators, including the recommended Mesen.

This happened using an everdrive n8 pro, OS version 2.12, with G revision PPU and CPU on a famicom motherboard HVC-CPU-07:

Not obviously a bug, but from a game design perspective, it is awkward that key counts don’t reset after dying and that keys respawn after entering, leaving a room. Way too easy to get infinite keys.

After clearing what I assume is “level 1”, I was softlocked in this screen, with my character spinning around in the middle of it, and no further inputs worked.

If the developer can debug the game, this looks like it could be a fun platformer.