Hello and welcome back.
I have had this 40K Blackstone Fortress Robot knocking about for a couple of years. My first problem was how to paint it. At first I was going to go for an ancient machine look with lots of rust as just another hazard of digging through the ruins.
Another idea was to assign it to a particular faction giving it a paint job suitable for the faction. Then I settled on painting a standard military colour so it can be used with what ever faction. The old bot sat in some bunker or cupboard forgotten until someone charges it up and press the KILL button.
This robot will be useful to supply some fire support to my Sci Fi factions and some of my post apocalyptic factions.
Thanks for looking and stay safe out there.