Any node that did this would have their stake slashed by the rest of the network, because it would be easy to prove that the chain was invalid. The network fina

Any node that did this would have their stake slashed by the rest of the network, because it would be easy to prove that the chain was invalid. The network finalizes the blocks that are added to the chain, there are no deep chain reorgs like in bitcoin - so any significant alternate history is easily identified.