IOG unveiled Cardinal, first protocol allowing native Bitcoin UTXOs to circulate in Cardano DeFi market.Cardinal uses MuSig2 to secure Bitcoin, HTLC for reclaiming funds, and eUTXO smart contracts on Cardano.Ordinals crossing the bridge retain provenance, becoming programmable assets in DeFi without losing ownership.Cardinal aims to reduce risks compared to custodial bridges, offering interoperability while maintaining security.