X-Men: Dark Phoenix Trailer Breakdown - 14 Things You Need To See
5. Magneto's New Brotherhood

Perhaps the most interesting shot of the Dark Phoenix trailer didn't actually involve the Phoenix. Instead, it features Magneto and his new brotherhood, with Beast having switched allegiances to join up with the Master of Magnetism and two other mutants.
This is where things get interesting; Andrew Stehlin plays Red Lotus, and Kota Eberhardt will play Selene, one of the oldest characters in the Marvel Universe and a character of key importance in the actual Dark Phoenix comic.
It certainly looks as though Xavier is struggling to keep his team together, as an image released by IGN shows Magneto flanked by Nightcrawler and Storm too. He's haemorrhaging teammates left, right and centre, and at this rate, it'll be a wonder if he has any left for the film's obligatory final battle.