All units with the Legiones Astartes (Emperor’s Children) special rule in an army that includes Fulgrim Transfigured must replace it with the Legiones Hereticus (Emperor’s Children) special rule. In addition you cannot include Fulgrim Transfigured in the same army as Fulgrim.
Building an army? Create, validate and share your list with New Recruit, army builder for (HH V2) Horus Heresy (2022) and many more games.
Try the builder