Here is all we know from John Warden regarding this new Generations line.
War for Cybertron line may include some previous molds, but intention is to give good representation of the characters.
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A lot of families in fan community, it’s exciting to bring them to the brand and share with kids, nieces, nephews. That doesn’t detract from Generations, War for Cybertron appealing more to the older fans and collectors.
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Power of the Primes ends in 2018. War for Cybertron starting in January 2019, no reveal of the new fiction yet so plenty of speculation welcome.
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Trilogy invites to speculate, not lead to an ecosystem – it’s a storytelling universe, as per Hasbro blueprint.
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Next chapter will be approached with fan feedback in mind – though cannot reveal yet. War for Cybertron is a new take on things, moving a little further away from the callbacks and throwbacks in POTP too, though story can feel a little more familiar.
So, any previous rumour of "evergreen" designs taking over generations, or Cyberverse, have been 100% debunked. It will be business as usual with the Generations line right down to the use of tooling and designs from previous lines. These will still be toys aimed at older kids and collectors and be centered around G1 characters. The fact that it may sound limited to non earth based alt modes does not really detract from anything when we currently have very few strictly earth based vehicles in this year's Generations line. As a further example that any character is still up for grabs, the main cast of More tha Meets the Eye had non earth designs, so the setting of this new chapter does not hinder to who we could get.
John Warden had also said that combiner and headmaster toy technology could resurface (as we saw with Power of the Primes) so any G1 character you did not get yet has a chance of coming, including combiners you did not get yet. At this point, everything is back on the table with three more lines to fill with toys.
As John Warden has invited this fanbase to do, speculate away!