Years before Marvel announced the Morbius.
From alien shapeshifters to reality-bending wizards and living planets, the MCU has come a long way since a man in a metal suit was its most groundbreaking innovation. But now that the Infinity Saga has concluded, there are still some important groups of characters from the comics that have yet to be officially introduced in the movies, such as the mutants and the Atlanteans. The bright side is that the MCU's lore keeps expanding at an accelerated rate with every movie that comes out, and in 2017, Thor: Ragnarok contributed in large part to this expansion. Director Taika Waititi's reshaping of the easter eggs include clues about the existence of Beta Ray Bill and the Korbinites, Ares and the Olympians, and Blade's bloodsucking adversaries: vampires.
The tease in question occurs when Thor (Chris Hemsworth) and Korg (played by Waititi himself) are getting prepared for battle in the intergalactic Contest of Champions. While What We Do In The Shadows, a mockumentary about three vampires who share an apartment. However, it also suggests that the concept of blood-sucking, undead creatures is a universal idea in the MCU.
If this line had been uttered by any terrestrial character or by any alien with ing knowledge of Earth's culture, the line would simply have been a throwaway joke — but the detail that makes it relevant to the introduction of vampires in the MCU is that it's coming from Korg, an exotic character who doesn't have the slightest insight into Earth folklore. This also doesn't mean that Korg has personally crossed paths with them, but it does suggest that many other distant alien races must share roughly the same knowledge of what vampires are and their traditional characteristics, including being vulnerable to a stake driven into the heart. If they aren't a present threat in distant worlds like Sakaar or Korg's home planet Ria, then they surely must have existed somewhere in order to become a universal legend.
Part of what makes the Marvel Cinematic Universe so successful is not only its ability to plan ahead but also its ability to transform previous offhand details into key elements of future movies. Just like Loki's Scepter turned out to contain an Infinity Stone and the Infinity Gauntlet in Odin's Vault turned out to be a fake, the widespread knowledge of the vampiric legend could become an essential foundation for their introduction in the MCU — or at least the answer to why they haven't shown up yet. Taika Waititi's self-aware reference is a fun easter egg in Thor: Ragnarok, but it could very well be the starting point for Blade.
