==History==
===Unknown Infiltrator Squad===
After the return of [[Roboute Guilliman]], the fifth squad was seen fighting as a fully-[[Primaris]] [[Infiltrator Squad]] alongside their [[Primarch]] and [[Chief Librarian]] [[Tigurius]], defending a position against [[Tyranids]] of [[Hive Fleet Behemoth]].{{Fn|1a}}
==Sources==
* 1: [[Codex Supplement: Ultramarines (8th Edition)]]