Here's something I did during lockdown a few years ago. For this particular conversion, I accidentally ended up with two identical Kriza Boracs powered suits from the Nomads Tunguska Jurisdictional Command box set (the first one I picked up as a loose single on ebay, the second is from a box set). I'm not the type who likes more than one of a particular pose in my squads, so I knew I had to modify one of them.
So after digging through my bits boxes, I found a bunch of Gundam kit weapons in various scales. One of the smaller weapons ended up being a decent sized rocket launcher type weapon for this mini, so that's what I went with.
I wanted to change the basic pose, but I was in no mood to butcher those legs. And one of the other Kriza Boracs powered suits from a different box set is in a running and leaning forward pose, so I didn't want to duplicate that pose either. So I came up with the idea of putting something larger than the ammo crate under its right foot, changing the geometry and perspective of the pose.
Once I removed the crate from the foot (the right leg with crate is a single piece), I had to come up with something to replace it. Another crate? Boring. A rock? Nah. Oh, what's this?... A 1/144 scale Victory Gundam head leftover from a weapons set box? Sure!
So I got all the parts cleaned and assembled, and I did a bunch of tweaking to the arms and their sockets with some dremel work (using 0.093" diamater tip bits). Then I built a custom weapon from some other bits, and... well, here...
(I built both minis at the same time; the one on the left is stock standard, and the one on the right is the conversion).
Once I determined the optimal position of the Gundam head to allow the powersuit's right foot to have the most contact area, I went about making a divot in the head in the shape of the footprint. This allowed for a solid glue bond, and also makes it look like he's crushing into the head. I then added a bunch of battle damage to the head.
I made a slight miscalculation, and the left foot ended up with a 0.050" gap between it and the surface of the base. But I didn't want to remove any more of the Gundam head for fear of losing some of the detail and the overall impact of it being the head of a substantially larger mech. So I found another panel piece (part of a foot plate) and sanded it down until I could fill the gap.
And in keeping with the rocket launcher theme, I added some ammo rounds the hip area of the powersuit.
I think if I'm ever in a game where we're playing anime-style mecha, I might just use this guy as my mech.