I’ve been working on Edddy, a map editor that allows you to create worlds using pre-made sets of blocks. If you want to give it a try, you can find the controls here.
Its intended use is to build maps for A-Mazing Urho, KO, OGTatt and Blip 'n Blup. Edddy draws inspiration from Blender, Tiled and other open creation software.
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Edddy by LucKey Productions
A block-based map editor