> For the complete documentation index, see [llms.txt](https://xtop-pet.gitbook.io/xtoppet-whitepaper/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://xtop-pet.gitbook.io/xtoppet-whitepaper/what-is-xtoppet/core-gameplay/pet-nurturing-and-upgrading.md).

# Pet Nurturing and Upgrading

* **Buying pets:** New players can use XTO to purchase their initial pets. As the game progresses, players can also buy higher-level pets.
* **Feeding pets:** The growth of pets depends on regular feeding. Players need to purchase various types of food to maintain their pets' health and energy. Food types include carrots, milk, bread, etc., each with different energy values and costs.
* **Manual upgrading:** In addition to natural upgrades through regular feeding, players can opt to use XTO to manually upgrade their pets to the next level, rapidly enhancing their capabilities.