It's really impressive! I wanted to found something like that for years, would you mind sharing the code? I can't find the Construct 2 BulletML plugin...
Viewing post in BulletHell Tester v1 comments
Hello, sadly the plugin was for sale. We could contact author and make it free with https://opencollective.com/construct-community
I will try to contact him. I could also make some screenshots but without the plugin its worthless.