Tortoise

In the Rail Nomads Camp north of the Hobo Camp can a tipped over tortoise be found.

The player can interact with it, flipping it over or not. Alternatively he can use animal whisperer in order to turn itself on its own. Doing so will send the tortoise on a lengthy journey to the waterfall, located at the beginning south-east river (Where the radio tower and various animals can be found.) There it will than die and reveal a hidden burial of rare and useful items, if the player has a shovel ready to be used.

The wiki hints that flipping over the tortoise forcefully will cause in an event that will cause killer robots to annihilate the nomad camp. No information is given on possible outcomes of a successful animal whisperer check. This is however not implemented.