The enemy "Yadotsuri" from the game "Tomato Adventure" for the GBA. Pictured on the left is its appearance in the cancelled GBC version of the game, originally called "Gimmick Land."

Because of this, Doki Doki Panic never received a cartridge release, but instead as a floppy for the FDS.
The main characters Papa, Mama, Lina, Imajin, Poki, and Piki were all created by Fuji TV and used in the event.

It's pretty common knowledge about Super Mario Bros. 2 being a reskin of the Famicom game Doki Doki Panic, but what's less known is that the game itself was made as a tie in for Yume Kōjō '87, a festival in Japan.
It was partially developed by Fuji TV, a broadcasting company in Japan.

Family Basic V3 came with some prebuilt games you could use as inspiration. Of note are "Drill Tank" which uses some Koopa sprites, and "Mario World", a very basic Lode Runner clone where you have to collect numbers in order while avoiding Sidesteppers.

Some EXTREMELY obscure sprites of Mario exist in Family Basic, a programming tool for the Famicom by Hudson and Nintendo. There's a lot of goodies here but the real winner here are these playable Pauline sprites they made!