> For the complete documentation index, see [llms.txt](https://docs.casperpunks.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.casperpunks.io/ghost-town/evolving-and-usdexp.md).

# Evolving and $EXP

Is your punk the rarest of all?

Evolve your CasperPunks to be the rarest of all.

CasperPunks with the same type will be able to produce new ones of the same type.

You will need to use $EXP and $BOO tokens to breed new CasperPunks.

But just like how rare you are in this world, your CasperPunks are as well.

The probability of you succeeding in Evolving your CasperPunks is small, so be ready to send them evolving only once you are confident.

You can increase the probability of success of evolving by upgrading your [Intelligence](/ghost-town/usdexp.md).

It will take 1 week to find out your results. There will be no limits to evolving your CasperPunks.

Upon failure to evolve your CasperPunks, your original CasperPunks will be sent back to your wallets but their stats will set to normal. You will also have spent your $EXP and $BOO tokens, so only evolve when you are ready.

<figure><img src="https://2828204673-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FhsHyF5q3yumacr6HWEUy%2Fuploads%2Fp4JOiAIPHcLPw3wFVfMY%2Fevolveing1.png?alt=media&amp;token=29de7307-4869-4c09-bff9-a21a394941b7" alt=""><figcaption></figcaption></figure>