The Biome Wand is a handy little tool that allows you to change any biome to whatever you want it to be. It won’t change the whole biome all at once as it only changes within a designated radius that you can pick by shift + Right clicking while holding the wand.
You’ll need to gather samples of whatever biome you want to change the current biome to first. Then you just have to craft a Biome Sample and right click in the desired biome. Then attach it to the wand in a crafting bench and click away!
You’ll notice a change instantly in the environment and all natural effects will apply. You’ll also notice the radius that changes so obviously you’ll need many biome wands to change a much larger area. But luckily the samples can be reused over and over and you will get a decent amount of changes over the life of the wand.
You can even mix and match biomes that don’t normally belong next to each other!