WarioWare D.I.Y.
Used by 2 peopleen.wikipedia.org ↗

“I've used the music maker from WarioWare DIY to make music for a game jam once.”
Eli Rainsberry Interview, Composer, sound artist · via Uses This 
“I've been frustrated with software lately so I started making my own drawing tools, hoping to turn the process of making games into something like WarioWare D.I.Y.”
Fernando Ramallo Interview, Coder, designer, visual artist · via Uses This