(Careful not to use the word Immutable as Immutability is not absolute)
In Bitcoin, Proof of Work is used to make it computationally difficult to edit an existing block due to the fact that the subsequent blocks also have to be REmined, requiring a lot of compute power. Am I correct in assuming that in Multichain, once a block is edited, the subsequent blocks need to be REmined in a round-robin fashion?
If so, why does a block in Multichain still contain a difficulty level and a nonce? I thought these properties were associated to Proof of Work.