From the announcement:
We have been diligently working away on these rules for the last year or so, running them through lots of playtesting with our teams out in the wider world. We are very happy with a lot of the central Dark Age rules as they are, but there were a few things that we needed to evolve, to adapt, or to replace. We always strive for clarity in our rules writing – aiming definitely for ‘rules as written’ over ‘rules as intended’ – and the 2017 Master Rules no doubt hits closest to that mark of any of the previous editions.
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