> For the complete documentation index, see [llms.txt](https://distrup7ed.gitbook.io/bob-chain/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://distrup7ed.gitbook.io/bob-chain/probabilities-and-power/upgrades.md).

# Upgrades

## Heroes upgrade chances and costs

Each hero has a total cost of upgrade equal to his combat power divided by 3. Whenever a hero is successfully upgraded, it will acquire the combat power described in the previous section. 

* Lev 1, 55% success chances
* Lev 2, 52% success chances
* Lev 3, 50% success chances
* Lev 4, 45% success chances
* Lev 5, 40% success chances
* Lev 6, 30% success chances
* Lev 7, 25% success chances

**Remember**: if you have G-Crystals, you can use them to save your heroes from destruction in case the upgrade fails! Any level of hero can find G-Crystals in arenas, or players can simply buy them on the open market in the marketplace section