Utilizing @Coockie1173's toolchain for parsing and editting the BM64 ROM, this C# tool allows you to extract, inspect and edit level-maps from Bomberman 64. The tool provides a 3D viewport, a layered 2D viewport as well as a detailed sector viewport, which makes it more comfortable to navigate existing maps. Through the implemented tile-selector and various other tiling tools, you can then edit the maps as you wish, or start from a blank slate. If you are happy with your creations, you can either directly save your changes to the ROM file, or export them to OBJ for further adjustments in CAD software like Blender.
