>>96310465
>that artwork

Mortarion didn't wear a rebreather until he became a daemon prince, instead he had a collar fitted with a special, rebreather-like front that spewed gasses from his homeworld. Whoever drew this is a tertiary.

>b-but in some HH artwork he wears a rebreather!!!

SHUT THE FUCK UP, HIS MODEL DOESN'T COME WITH A REBREATHER OPTION, TERTIARY.