The arrival of Cities of Sigmar does mean a handful of Order units will be leaving the range and becoming Warhammer Legends later this year. We’ll be providing a full list of which ones closer to the time. The number of units available in the book is still vast, with loads of warscrolls. What’s more, each City of Sigmar can enlist units from Battletome: Stormcast Eternals into their main force, while Tempest’s Eye and The Living City can draw on aid from the Kharadron Overlords and Sylvaneth, respectively, as full members of your army that share your allegiance abilities. Here’s rules writer Sam Pearson with his thoughts on the book…
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A lot less miniatures, go play Stormcasts, no thanks.

This is just a reduction and purge of the range that has been ongoing for a while. Buy the new stuff, which to be fair to GW is their business.