Pre-Imperium Techno barbarians

A unit of 5 techno-barbarians, painted without faction markings so they can be used as either chaos marines or loyalists.

From Lexicanum:

Techno-barbarians is the name given to the warriors who battled over the ruins of Terra during the Age of Strife. They formed the troops of the warlords who dominated Terra during the period, and were equipped with a primitive form of powered armor which would become the basis for the developments of Space Marine armor.

The Emperor arose in the later part of the Age of Strife to reunify Terra. Under his leadership his army conquered the other warring techno-barbarian factions.

and this segment gave the archaic looking and odd designs a thumbs up;

 This early armour was produced on a completely local basis and as such individual suits varied heavily and their exact designs were often a matter of personal taste.

 White Dwarf 129 (UK), Space Marine Armour by Rick Priestley, reprinted in Warhammer 40,000: Compilation

All backpacks are from the Chaos marine spru, to make them look as old fashioned as possible.

The old plastic fantasy chaos warrior helmet made me think of thunder armour, because most of the pictures of it show a topknot;

I have been meaning to see how the chaos marine and old chaos warrior plastic kits fit together for some time now, and I found the proportions to be similar. With the leader and the marine below I attempted to sculpt the legs myself with milliput, but in the end I just opted for the easier way; cutting the marine and warrior legs at the calf and sticking them together.

The biggest issue with fitting the kits together was cutting and repositioning the arms. Most fantasy figures have outstretched arms for brandishing hand weapons, whereas a lot of 40k ones require arms that 'hug' a gun closer to the body.

After this miniature came out a little short looking I tried bulking out the joins with plasticard to add height and width.

  Finally, here's a shot of a couple of WIP cultists / renegade guard, in anticipation of the new unit for Chaos in 40k. They're mostly fantasy empire militia, but I'll be hunting for any scraps to make them suit the 40k universe.