Super Mario Advance 4 gets unofficial 3DS port in new proof of concept homebrew release
Why emulate Super Mario Advance 4, when you can play it natively, on your 3DS? A user named Mythical-Atlas has created a homebrew port of the game to the Nintendo 3DS, which features custom-written code to get all the audio and handling functions working correctly through CTR User Library. Right now, it only contains the first level of Super Mario Bros. 3, but the dev claims that the homebrew has "modular support for multiple different levels". They're also working on other 3DS homebrew projects, and this port will be the basis for them.
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