RBTC is the BTC-pegged native token of RSK, the network on which Sovryn is built. RBTC is an exact 1:1 peg with BTC. (1 RBTC = 1 BTC) When you transfer bitcoin into RSK, your bitcoin is locked and the equivalent amount released as RBTC on RSK. Using RBTC, you can lend, borrow, and trade on Sovryn. In addition, all fees are paid in RBTC, so you don't need a separate asset just for transaction fees.

RSK is a merged-mined Bitcoin Layer-2 sidechain that provides for smart contract functionality using bitcoin as the native asset. RSK is the most permissionless and censorship-resistant Bitcoin sidechain:

• RSK is permissionless. The consensus mechanism is merged-mined PoW with over 60% of Bitcoin's hashpower mining RSK as of February 2022. This means that RSK is mined by more hashpower than any other chain, except Bitcoin itself.
• RSK's two-way peg mechanism (called PoWpeg) is probably the most secure peg based on a multisig system in the crypto world. It uses a combination of HSMs and SPV proofs with multiple different functionaries. It layers PoW (through SPV proofs) over HSM security, providing additive security and decentralization. Unlike Liquid, it is permissionless and highly censorship resistant.
• RSK sidechain is constantly improving the two-way peg. In the next iteration, Bitcoin miners will directly participate, making the peg even less federated and even more tightly coupled with Bitcoin PoW.

Learn more:

FastBTC Relay

RSK - FAQs

RSK: Defi on Bitcoin

Understanding RSK and RBTC