There is no shortage of options for making video games without knowing how to program. It all depends on the genre you want to create: you can use Construct and Game Maker for platformers, PuzzleScript for puzzle games, Ren'Py for visual novels and RPG Maker for role-playing games, among many others. You even have an engine for making NES games that work on the original console! But until recently, there was nothing for making adventure games for Nintendo's little handheld, the Game Boy. All that has changed thanks to GB Studio, a SUPER simple tool and, best of all, 100% free and open source.
GB Studio is a visual editor for creating Game Boy video games that requires no programming knowledge, and lets you build a ROM that you can run on the original console or on an emulator in minutes. Behind its development is Chris Maltby, a programmer who, after creating a series of scripts to participate in a game jam, decided to combine all those tools into an application that anyone could use.
The engine uses visual scripts (pre-programmed) to simplify the process, as well as a series of tools for building levels (which only need a mouse to work). Graphics can be imported in PNG (following the Game Boy color palette) and the final result is delivered in a ROM that can be played on the original console or on an emulator. Thanks to the tool's native emulator, you can also export the game in HTML5 and hang it on any website. You can find more details on the official GB Studio website.
Of course, with so much simplification and independence from code, don't think you can build a too complex game. GB Studios works very well for designing top-down adventures, in JRPG style, but little else. If you want to get an idea of what you can create with this delicious engine, click here to see the game created by Chris Maltby for the aforementioned game jam and which now serves as an example. GB Studios is available for Windows, Linux and MacOS, so you have no excuse not to give it a try. You even have a reference tutorial. And don't forget to check the official GB Studio site for updates.
Official site: GB Studios