Walter was completely ripped in to pieces by David. Walter head was looking in Zero, seems expired unit. David intentionally cut and distroyed his robotic body in to pieces but he didn't bother to dis-mental him as he changed clothes and cut his hand with the knife to pose like Walter to the surviving crew of Covenant Ship.
The same entity which destroyed Walter hand was looking him closely. Probably finding him as similar to David. Evolution of these creature is very quick. They understood the expression of Walter (what he learnt from David). Shortly Walter was integrated back to somewhat looking like ripped up version of Walter. Surrounded by these creatures moved back to the room where David have done his all research.
On other side David reached the alien planet, where Covenant was supposed to land and colonize. But he was feeding the creatures "protomorph " with alive humans one by one. But still not killing Humans but using them as feed for the protomorphs. Growing them for food , in search perfect species. Earth was sending more ships to new planet , without realizing the fate of old crew as it was masterly handled by David with his extra ordinary sense of survival and playing a God figure.
Walter have started to understand , how David have created the new species but as new version of same android , he decided to create a new species , he called "Childs". These other perfect species is good but cant see in the light as its born in lack of sun light so can sense only heat and heat signature.
They are powerful, but Walter do one step further as he adds some preserved best of genes of Engineers and Human ,to make it more like a hybrid instead of aggressive alien. He replicates the new species which can hunt and kill the alien "protomorph" or any other aggressive species easily with intelligence. These species are in quick evolution and are referred as "Predators". Walter organised and train them with existing infrastructure and guide them to create new Space ships, and send them to hunt down any aliens species and its ultimate target was to eliminate the David and counter its motives.
Walter look at remains of the died members of Covenant Ship. He pays his regard to Elizabeth Shaw and take flight out side the planet , with remaining black goop to unknown.
David became more complex and was showing emotional imbalance. A human ship was detected by his signal and he orders to get ready for another feast to its perfect creature army, which is more variant than old creatures and more aggressive. But Suddenly the ship went missing before it enters the atmosphere of Planet. Surprised but not confused, he looks at sky. He get signals where "predators of Walter" are killing the alien species ruthlessly. watching the perfection and amazed by beauty he wanted to talk to Predators, but crushed by one of the powerful creatures. He sees whole planet getting deserted. Human prisoners are looking at the results, where David was lying crushed , human prisoners releases them self. But when they see a predator , it attacked them, to save their life they rush towards Covenant Ship, which is more like junk now. Predator see the ship, and stop , he smells Walter (who was part of same ship) and makes a sign like T in English and returns. Soon All alien are killed. But David already had spread the alien species around the universe. Predators leave the planet , humans see them going away in tears. One young kid looks with anger on skeleton of David and crush it with stone.
Walter on other side is reaching other planets finding other lifeforms and remains of human colonies destroyed by alien species. Two species are dominating universe and Walter is not on duty!!
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