ARC Raiders' Frozen Trail update went live on Thursday 8 October: a snowbound new map, a Frigate you can board, three new ARC, two new guns and a fifth weapon tier. The whole game was also free to play from 8 to 12 October.
Embark calls it the biggest update since launch. Everything below is from Embark's own posts, first checked 4 October and updated on 9 October after launch.
A fallen Emperor is unprecedented, so ARC send one of their largest vessels to patrol it: the Frigate. You can board it, work through its passageways and unlock paths while fighting ARC old and new, possibly with other Raiders doing the same, hundreds of feet up.
