What If BTC Maxis Block OP_CAT? We're Not cooked. There are several approaches: Multisig: The OG solution. Lock funds with a federation of signers. Simple but has the worst security - if enough signers collude, your funds are toast. Think of it as trusting a committee of hall monitors not to steal your lunch money. BitVM: The current challenger. Uses fraud proofs where one honest participant can call out cheaters. Much better security (only need 1 honest person), but it's capital inefficient. Operators front user withdrawals and wait for challenge periods to get reimbursed. It's like paying your friend's bar tab and hoping they'll pay you back after a 2-week waiting period. ColliderVM: The new hotness. Works without fraud proofs or soft forks by using a clever mathematical trick with hash collisions. Instead of constantly watching for cheaters, it relies on the extreme difficulty of finding specific mathematical "keys" to ensure honest behavior. Pre-arranges possible execution paths, making stateful computation possible without protocol changes. The magic of ColliderVM is it could give us complex applications on Bitcoin's rigid base layer without begging maxis for protocol upgrades. We're talking bridges to other chains, verifiable computation, and advanced financial tools - all while preserving Bitcoin's simplicity. Bitcoin may be a basic calculator, but these approaches are turning it into a programmable computer. ColliderVM might be the least painful path forward if the OP_CAT dream doesn't materialize.