So I rewatched the last trailer, and there is a shot of one of the Viltrumites getting hit, with a pink background behind him. Almost all other shots were from episodes 1-2, so it’s fair to assume only parts of part 1 were used in this trailer.

So considering Nolan is one of the most popular characters, considering that this season will feature the VA for battle beast, and considering part 1 needs to end on a cliffhanger to keep hype alive for part 2, I am guessing that episode 4 will have the big brawl in space.