Speed Build Kit

This modpack contains many tools that allow you to build really quick, you can build as quick as dozens of vanilla builders, it has lottweaks, a mod that allows you to quickly switch between blocks, you can get the block you want within 2 seconds, I'm not joking, also you have the Command Macros mod, which allows you to bind any command you want to any key combination, you can bind worldedit commands and you can make stuff really quick, apart from worldedit, this modpack contains WorldEdit CUI, which allows you to view your WorldEdit selection, you also have Litematica, also, this modpack contains the Effortless Buildings mod, which allows you to build many times quicker, you can create spheres, giant cubes, walls, stairs, cylinders, within seconds, any size you want, without typing any command, it has some other features like Iris Shaders so you can give Minecraft a fancier look, it has Xaero's Minimap so you can have a better navigation in large maps and Zoomify which gives you a zoom option just like OptiFine.

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The ultimate 3D to minecraft exporter with interactive preview inside blender, you can export in seconds: BlockBlender to Minecraft .schem (gumroad.com)