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The method used to tame bugs in Grounded is relatively simple: Just feed them with Slurries. Generally a couple of Slurries is enough to tame a bug, but sometimes it takes a few extra. Different bugs might like different kinds of Slurry, too, so you might want to try out a different types. Once the insect is happy it will be ready to be domesticated
When it comes to taming, you are going to need Slurries. You can make these by using the grinder. Simply place plant fiber and mushrooms in it to get Plant Slurries and Mushroom Slurries in return. Once you find the bug you want to tame, drop two Slurries in front of it. It helps to make sure that there are no other bugs around first. So far, you can only tame Weevils and Aphids. Also Weevils prefer Mushroom Slurries, while Aphids like Plant Slurries better.