> ## Documentation Index
> Fetch the complete documentation index at: https://sequence-0fb8d9e6-api_docs.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Using Sequence's Subsystems

> Documentation for Unreal SDK API for the Sequence Wallet infrastructure stack for web3 gaming.

Our Unreal SDK includes a set of Subsystems for seamless Blueprint integration. You can use them in any of your
Blueprints, such as in your Game's User Profile or Login Screen. To handle asynchronous requests, make sure to
assign event listeners to the calls you make.

## Sequence Sessions

Use Sequence's Wallet Subsystem to create and manage user sessions, such as when they sign in with Email or Google.

<Frame caption="Subsystem Sessions">
  <img src="https://mintcdn.com/sequence-0fb8d9e6-api_docs/mFSme1NCuX8tg8YP/images/unreal/v1/subsystem_sessions.png?fit=max&auto=format&n=mFSme1NCuX8tg8YP&q=85&s=26ce3e2d31efd91ebe3017333a507b4a" width="1490" height="922" data-path="images/unreal/v1/subsystem_sessions.png" />
</Frame>

## Sequence Wallet

Use Sequence's Wallet Subsystem to send transactions or sign messages. Ensure the user has created a session beforehand.

<Frame caption="Subsystem Wallet">
  <img src="https://mintcdn.com/sequence-0fb8d9e6-api_docs/mFSme1NCuX8tg8YP/images/unreal/v1/subsystem_wallet.png?fit=max&auto=format&n=mFSme1NCuX8tg8YP&q=85&s=d76505d72c78d3a588bdccdf683ef238" width="1438" height="926" data-path="images/unreal/v1/subsystem_wallet.png" />
</Frame>

## Sequence Indexer

Use Sequence's Indexer Subsystem to retrieve user information, such as their balance or the tokens they own.

<Frame caption="Subsystem Indexer">
  <img src="https://mintcdn.com/sequence-0fb8d9e6-api_docs/mFSme1NCuX8tg8YP/images/unreal/v1/subsystem_indexer.png?fit=max&auto=format&n=mFSme1NCuX8tg8YP&q=85&s=8ce77124101d8b69d28054d52e1a42f2" width="1434" height="916" data-path="images/unreal/v1/subsystem_indexer.png" />
</Frame>

## Sequence Pay

Use Sequence's Pay Subsystem to access On-Ramp functionality and allow users to buy crypto using credit cards.

<Frame caption="Subsystem Pay">
  <img src="https://mintcdn.com/sequence-0fb8d9e6-api_docs/mFSme1NCuX8tg8YP/images/unreal/v1/subsystem_pay.png?fit=max&auto=format&n=mFSme1NCuX8tg8YP&q=85&s=29042320ff2b43d6b58943dada51ab77" width="1454" height="928" data-path="images/unreal/v1/subsystem_pay.png" />
</Frame>

## Sequence Utility

Use Sequence's Utility Subsystem for convenience functions that encapsulate common use cases into smaller Blueprint nodes.

<Frame caption="Subsystem Utils">
  <img src="https://mintcdn.com/sequence-0fb8d9e6-api_docs/mFSme1NCuX8tg8YP/images/unreal/v1/subsystem_utils.png?fit=max&auto=format&n=mFSme1NCuX8tg8YP&q=85&s=ea8319d69d28be6aa38774f1d060428f" width="1446" height="928" data-path="images/unreal/v1/subsystem_utils.png" />
</Frame>