# Testnet Beta

### Function Update

The Beta Testnet introduced three major updates for the bridge:

* Introduced two new roles: public operators and challengers
* Supported wider transaction range: `0.001 - 3 sBTC`
* Supported depositing to multiple chains: Ethereum Holesky, Plume, Monad, and more coming.

**Public Operators:** Individuals and institutions can apply for the operator roles in Beta Testnet. Multiple operators can help guarantee bridge service availability, and ensure a smooth bridging experience by  fronting sBTC (native BTC during mainnet) to users during withdrawal.

**Challengers:** They ensure the operator's honest behavior; anyone can permissionlessly become a Challenger. If an operator tries to steal user funds, challengers can dispute the transaction directly on Bitcoin. Bitcoin will be the ultimate judge to punish malicious operators directly.