The Excalibur reference in Eternals secretly set up a new Marvel Cinematic Universe connected to Black Knight. Through the exploration of human history over 7,000 years and the origins of the Eternals, Phase 4 used Eternals to plant many seeds that could be important for the future.
This includes the likelihood of setting up Namor's arrival in Black Panther: Wakanda Forever and introducing Thanos' brother Starfox (Harry Styles). These teases came as the MCU movie focused on its ten main Eternals
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