It may not be a real mech but this was always a favorite of mine from MW4. A couple requests later and I bumped it to the top of my list.
As always, this is meant for SLA/DLP printers, no guarantee it will work with FDM. Either mirror the file legpose3 for the other side or use on of the other poses for the other side. I've also included the legs components should you wish to create your own pose. Scaled in line with the MW:DA figures.
Edit 05/19/2019: Added three variants, and it's been brought to my attention that I have improperly scaled this for the Dark Age figures. As of now it is closer to 6mm scale.
Edit 05/23/2019: ankle joints has been thickened
Major Edit 05/24/2019. I'm going to do a rework of the legs of the Hellhound so stay tuned over the next few days. I'm going to print it out at a small scale myself before updating anything else to make sure it works.