This is the famous echidna after being requisitioned from the death korps by the INQUISITARII, in the quest for forbidden knowledge, both the inquisition and skitarii have overlapping goals. This army is the representation of that branch of the empire using forbidden tech in the name of the emperor.
The Inquisitarii requisition troops from the Astra MIlitarum, these troops represent the shift towards a more military style dress.
progress shot on the vanguards, airbrushing means I can work very quickly, which is good because I am an impatient man
The Echidna in its previous form: