Although not every node runs every computation, ALL nodes replicate all state in the network. This is to prevent any data availability problems .
If all worker nodes in Enigma network have the same copy of all secret contracts and their secret state, what’s the consensus algorithm of current release of Discovery without a blockchain between so many enclaves? How to deal with malicious node in the network?
In Discovery, consensus happened on Ethereum. Each worker was also essentially an Ethereum light client. Transactions were ordered on Ethereum through Task Records, and finalized through their accompanying task receipts. Workers in Enigma, as mentioned, replicated the data completely to avoid data availability problems, but they would only do so to mirror the task records/receipts on Ethereum.