David uses the Agent A0-3959X (the "Black Goo") as a biological weapon to wipe out the Engineers on Planet 4, later refining it to create the Protomorph —the precursor to the classic Xenomorph.
Speculation suggests a final film would lead directly into the events of the original 1979 Alien . Prometheus 2 Filmyzilla
Following Disney's acquisition of 20th Century Fox, the vast majority of the Alien and Prometheus catalog lives here. David uses the Agent A0-3959X (the "Black Goo")