Mushihimesama - how to get the restart bug

Regarding this video, Max S. asked me how to trigger the bug. It's quite simple to obtain it, but it seems like you just have to be lucky. It works in every mode and in every moment of the game with no particular setting.
If you restart the level sometimes one or some of the enemies on the screen remain in memory so they reappear at the beginning of the level too. This is particularly evident with bosses and mid-bosses, but it's also true for smaller enemies.

So, to put it short, just restart your game when facing the enemy you want to reappear and cross yor fingers. In my experience it happened a lot with the scorpion (well, it has to be said that I practiced it hundreds of times) and it's kinda funny but... Well, if you want to have serious practice it screws things a lot, forcing you to re-restart again.

Anyway, have fun!