Slingshot Bridge moves test assets onto Onyx Testnet and back. Open the app and choose Bridge. The page has two lanes. Both can run in either direction. Whether a lane is open, and the fee and capacity it will accept, are live values: read them on the form before you confirm.
| Lane | Chain | Chain ID | Assets in the app |
|---|---|---|---|
| Ethereum Sepolia | Sepolia ↔ Onyx Testnet | 11155111 | ETH and XCN |
| Robinhood Chain Testnet | Robinhood Chain Testnet ↔ Onyx Testnet | 46630 | ETH and TSLA |
Sepolia and Robinhood stay separate. A transfer always has Onyx Testnet on one side. When From is Onyx Testnet, To is a choice: Ethereum Sepolia or Robinhood Chain Testnet. The form does not offer a path that starts on Sepolia and finishes on Robinhood, or the reverse.
An older Robinhood-only address, https://app.testnet.onyx.org/#/bridge/robinhood-testnet, opens this same Bridge form with the Robinhood lane selected.
The app reads status from https://bridgeapi.testnet.onyx.org/api/v1. When the bridge is unavailable, the page says so and a new transfer should wait. The form shows the live fee, the amount you receive, the estimated time, the per-transaction maximum, the remaining capacity, and your balance of the selected token on both networks. Confirm only an amount the form still accepts.
Robinhood Chain Testnet: ETH and TSLA
In From, choose Robinhood Chain Testnet. The asset list then offers ETH and TSLA.
ETH on Robinhood Chain Testnet is native ETH. The deposit sends that ETH with the transfer. It does not ask for an ERC-20 approval. On Onyx you receive the Robinhood test ETH representation.
TSLA is the Robinhood testnet stock token, an ERC-20 on Robinhood Chain Testnet. The wallet approves the bridge for the amount you entered, then deposits that amount. On Onyx you receive the bridged TSLA test token. The test registry can limit which wallets may hold TSLA. If your wallet is outside that set, the app reports it before you sign.
The return trip starts on Onyx Testnet. You approve the Onyx representation of that same asset and confirm the withdrawal. Gas on Robinhood Chain Testnet is test ETH from the Robinhood faucet below. Gas on Onyx Testnet is test XCN from the Faucet.
Get test ETH and TSLA
Request both assets on Robinhood Chain Testnet from the Robinhood Chain Testnet Faucet. Add the network (Chain ID 46630) in the wallet, then enter the same address you will connect to Slingshot.
The faucet page says each request sends 0.01 test ETH and 5 of each stock token, including TSLA, and that a wallet can claim once every 24 hours. The same request also sends the faucet's other test stock tokens. This bridge lane uses the ETH and TSLA from that request. Amounts, the cooldown, and eligibility are set on the faucet page. Read them there before you submit.
Confirm the test ETH and TSLA balances on Chain ID 46630 before you open the bridge form. Test ETH pays gas for the Robinhood transaction. It is also the ETH you can bridge.
Add Robinhood Chain Testnet
Slingshot can submit this network to the wallet. You can also add it by hand:
| Setting | Value |
|---|---|
| Network name | Robinhood Chain Testnet |
| RPC URL | https://rpc.testnet.chain.robinhood.com |
| Chain ID | 46630 |
| Currency symbol | ETH |
| Explorer | https://explorer.testnet.chain.robinhood.com |
Check the chain with eth_chainId. The result must be 0xb626 (decimal 46630).
Which ETH you hold
ETH that arrived from Robinhood Chain Testnet and ETH that arrived from Ethereum Sepolia are different tokens on Onyx. Both can appear under an ETH label. Withdraw an asset on the same lane that deposited it. TSLA moves only on the Robinhood lane.
The app shows the fee and the amount you receive. Those values can include a percentage and a minimum fee. Gas on the source chain is extra. The quote on the confirmation screen is the amount you accept.
Robinhood transfers wait for source finality and then for the destination submission. The page shows the estimate and the live status. Keep it open through completion.
Ethereum Sepolia: ETH and XCN
In From, choose Ethereum Sepolia to move test ETH or test XCN between Sepolia (Chain ID 11155111) and Onyx Testnet.
- Sepolia ETH arrives on Onyx as the Sepolia-backed test ETH token. It is a different token from Robinhood ETH.
- Sepolia XCN and native test XCN on Onyx are the migration and bridge pair for this lane. Gas on Sepolia is Sepolia ETH. Gas on Onyx is test XCN.
- An ERC-20 deposit asks for an approval of the amount you are bridging, then the deposit itself. Native XCN on Onyx does not use an ERC-20 approval.
- Public Sepolia details and receipts are on https://sepolia.etherscan.io.
Onyx consensus transaction ids from this lane resolve on the validator dashboard.
While a transfer is open
- Read the source network, asset, amount, fee, and recipient in the wallet prompt.
- Submit one source transaction and wait.
- Use the in-app history for the same browser and the same site origin. History stored in one browser does not appear in another.
- If the status stays pending, leave that record in place. A second send creates a second transfer.
- If the page says the bridge is unavailable, wait until it accepts new transfers again. An already submitted transfer can still finish.