> For the complete documentation index, see [llms.txt](https://stargateprotocol.gitbook.io/stargate/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://stargateprotocol.gitbook.io/stargate/v2-developer-docs/integrate-with-stargate/token-types/hydra-ofts.md).

# Hydra (OFTs)

## Introduction

Hydra extends Stargate via Bridging as a Service (BaaS). With Hydra, Stargate enables users to transfer Hydra-wrapped versions of USDC, USDT, and ETH to Hydra chains (and between Hydra chains) quickly. 

## How Hydra Works

Hydra operates on a foundational principle where Stargate's core pools, residing on chains with native assets (e.g., Ethereum, Arbitrum, Optimism), are leveraged to facilitate asset bridging to newer chains lacking native assets. 

The minting of Hydra assets on Chain X uses the [Omnichain Fungible Tokens (OFT) Standard](https://docs.layerzero.network/v2/developers/evm/oft/native-transfer). This process is initiated when assets, such as USDC, are bridged from a core chain (e.g., Arbitrum) to a Hydra-enabled chain (referred to as Chain X in this context). The bridged assets are securely locked within Stargate’s pool contracts on the origin chain, while an equivalent asset is minted on Chain X.  A basic outline of the Hydra process goes as follows:

* When a user bridges USDC from Arbitrum to Chain X, their USDC assets get locked in the secure USDC pool on Arbitrum, and an asset minted on Chain X. 
* The user's USDC will always sit in an underlying Pool contract until they want to come back to Arbitrum (or any other Stargate core chain)

Since the asset minted on Chain X is an OFT, it can be horizontally composed across all current and future Hydra chains. The user could bridge from Chain X to Y, and always come back through Stargate to Arbitrum (or any other core chain). In other words, underlying assets are always redeemable from any core Stargate chain.

## Code

Hydra code lives in `StargateOFT.sol`. 

When you call `stargateType()` method from the`IStargate` interface on a Hydra asset it will return:

{% code fullWidth="true" %}

```solidity
StargateType.OFT
```

{% endcode %}


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