Thanks to
@Aeimnestos87 on Twitter, we now know who is producing Rampage Movie toys. He has shared a photo showing three packs from Lanard Toys for the figures.*I was able to track down some Walmart.come listings with official high resolution in-package photos as well, giving us a look at even more sets. Each monster is part of a special set, much like their Kong: Skull Island toys. As with the Kong sets, these appear to be based on their The Corps toy line, putting these about 3.75″ scale. These include:
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