From what I've read recently, actually, what became Doki Doki Panic was supposed to be Mario 2 after all.
Here's a couple of links I've found:
Post #740817
- Author
- Leonardo
- Parent topic
- Video Games - a general discussion thread
- Link to post in topic
- https://originaltrilogy.com/post/id/740817/action/topic#740817
- Date created
- 12-Dec-2014, 5:01 PM