MCU: 10 Cosmic Villains For Phase 4
7. The Builders
The Builders are the oldest race in the Marvel Universe and they see themselves as administrators of all life within it, as well as space and time. During the events of the recent Infinity storyline, the Universe is seen to The Builders as incorrect, contaminated and in need of fixing.
From this point on The Builders begin to treat the Universe as one big Bonsai plant that they could cut bits off here and there to help stem the problems they perceive within it. They destroy entire worlds, bring others under their heel, and even try and make planet Earth sentient.
The Builders would be an excellent foil for the MCU. It could give Marvel and James Gunn the creative freedom to make entirely new worlds that could be under the control of The Builders. As we've seen, Thanos has his own genocidal ideas for fixing the Universe but The Builders prefer a more surgical and methodical approach. This could bring them into direct conflict with not only our heroes, but Thanos too, as his ideology is challenged by these powerful beings.
It would allow Marvel to unite the Avengers with cosmic heroes and species they may not previously have encountered. We know the heroes are out there, Beta Ray Bill was referenced in Thor: Ragnarok and we had several nods to the original Guardians of the Galaxy in Guardians Vol. 2.