HECO-SubGame Cross-chain swap manual（Tokenpocket & Decktop)

7 min readJul 16, 2021

SubGame is a Polkadot-based mainnet that also has cross-chain tokens on Ethereum and Huobi ECO Chain (HECO). SubGame Bridge is your go-to place to swap your SGB between different blockchain networks. Let us walk you through the setup and swap process.

First off, swapping on mobile is easier than on desktop because after TokenPocket wallet supported SubGame mainnet, you can swap SGB using just one app.

TokenPocket download links:

Android: https://play.google.com/store/apps/details?id=vip.mytokenpocket

iOS: https://apps.apple.com/us/app/tokenpocket-crypto-defi/id1436028697

I. Mobile

A. HECO-SGB to mainnet SGB

1. Open your TokenPocket app and create or add a HECO address. If you already have an Ethereum address imported, you can sync it to HECO Chain:

tap the “Add Wallet” button (“+”) at the top right — “HECO Chain” — “Import Wallet” — “One-Step Sync” — “Ethereum BlockChain” — “Synchronize”. Then you will have access to your existing ETH address on HECO Chain.

2. To switch between your addresses on different networks, tap the blue button with the address name at the top left and scroll down to the desired network.

3. Go to your HECO Chain address. If you haven’t added SGB token yet, tap the “+” button to the right above your HT balance. You can either search for “SGB” or select “Custom token” — “Add token” — enter 0x7f8AB1593f84B0C450385a3f70e921cB796401Ba under “Account”. The token symbol is SGB; there are 6 decimals (both should appear automatically after you paste the contract address). Note: if you add SGB from search, make sure the token contract address you see is 0x7f8AB1593f84B0C450385a3f70e921cB796401Ba

4. Deposit your HECO-SGB to your HECO Chain address.

HECO-SGB in the HECO Chain asset balance

Note: On HECO Chain, you need Huobi Tokens (HT) to pay for gas in transactions, similarly like you need ETH for transactions on Ethereum. For places where you can buy HT, please visit CoinGecko or CoinMarketCap.

5. Set up a SubGame mainnet address: on the “Assets” screen, tap the network switch button — find the SubGame icon — tap “Add Wallet” — create or import a SubGame mainnet address (if you create a new address, make sure to back up your mnemonic phrase/seed to a safe place).

Right now, you are ready to swap HECO SGB to mainnet SGB!

6. Tap “Discover” at the bottom of TokenPocket main screen — go to DApp Browser — search for “SubGame Bridge” or visit https://subgamebridge.io:

7. Tap “Exchange Now” — select “Huobi ECO” above — tap your HECO address — wait till you see “Success to connect Huobi ECO”. Subgame is automatically selected below:

8. Tap “Select Crypto to Exchange” — select your SubGame address under “To Address” — enter the “Send Amount”

Note: Make sure to swap amounts within the minimum–maximum limits. If you see 0 under “Maximum”, than the contract has no more tokens left to swap.

Mind the minimum and maximum swap amounts

9. Tap “Submit” and review the transaction details. You can customize gas fee when you tap “Gas”. Tap “Confirm payment” and enter your HECO Chain address password.

10. When your swap is successful, you will see “Transaction Completed” message and your swap details.

You can check the transaction details under “Transfer Record”:

Your mainnet SGB balance will update after a few moments:

B. Mainnet SGB to HECO-SGB

The process is similar to the above.

1. Tap “Discover” at the bottom of TokenPocket main screen — go to DApp Browser — search for “SubGame Bridge” or visit https://subgamebridge.io.

2. Tap “Exchange Now” — select SubGame above and wait till you see “Success to connect SubGame”. Select Huobi ECO below and tap “Select Crypto to Exchange”:

3. Select your HECO Chain address under “To Address” — enter the “Send Amount”.

Note: On SubGame mainnet, transaction fees are paid in SGB, so you won’t be able to swap all your balance. Enter an amount that is slightly smaller than your total balance. The fees will be deducted from this amount, not added to it.

4. Tap “Submit” — review the transaction details and tap “Confirm” (gas fee settings are not available here) — enter your SubGame address password:

5. First, you will see “Transfer Submitted,” then “Transaction completed”:

Your HECO-SGB must arrive shortly:

II. Desktop

A. HECO-SGB to mainnet SGB

To swap SGB on desktop, you will need Chrome or Firefox with two extensions (MetaMask, polkadot{.js}) and the Polkadot/Substrate Portal:

MetaMask is the place to operate SGB on HECO: https://metamask.io/download.html

· after you installed MetaMask, open it, create or import your HECO (Ethereum) address to it (if you create a new address, make sure to back up your mnemonic phrase/seed to a safe place);

· click the round user picture — Settings — Networks — Add Network to set up HECO:
Network Name: HECO
New RPC URL: https://http-mainnet-node.huobichain.com
Chain ID: 128
Currency Symbol: HT
Block Explorer URL: https://hecoinfo.com

To switch networks, click the button next to the round user picture saying “Ethereum Mainnet” and choose HECO from the list:

polkadot{.js} is a counterparty DApp for MetaMask during swaps through Subgame mainnet: https://polkadot.js.org/extension/

after you installed polkadot{.js}, open it and create or import your address to it (if you create a new address, make sure to back up your mnemonic phrase/seed to a safe place):

Click “+” in the right upper corner to create or import an account

Now you have a Polkadot address. It can look like a different address on different Polkadot-based chains

The Polkadot/Substrate Portal https://polkadot.js.org/apps/#/explorer is the place where you can see SubGame mainnet and your Polkadot address in the correct SubGame’s format.

· go to https://polkadot.js.org/apps/#/accounts and click “Add account”