In response to post #25824664. #25824914, #25825809, #25825919, #25826019, #25826209, #25826354, #25826574, #25828999, #25830289, #25830979, #25831614, #25832299, #25832644 are all replies on the same post. She claimed that Fallout 4 is using a completely new engine: "This version uses a brand new engine built from the ground up to take advantage of the power of next gen systems. Absolutely everything is new, and no assets or scrips are being used from Fallout 3/NV or Skyrim." From what I saw from the trailer it's more like a modified Gamebryo engine than a new one to me, but with tweaks to lighting and animations, that's all. But I'm Ok with it since this way modders will have an easier time modding it.