While trying to find the pricey Yamato version of the Starship Troopers Marauder (movie version)…I found that they have a static model for much cheaper. For right about $20 USD shipped you get all three movies plus this monster:
Not my pic…sorry for the fuzziness. It looks great in person. Will probably need to be based for gaming purposes. It towers in at 8 inches. There's a rotary cannon for one arm and a cross shaped shotgun for the other. The latter looks more like an energy weapon really. Plus there are guns on the shoulders.
Now these guys are 7.25" and are poly-resin…so you will want to make sure they don't fall over:
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Normally they are called "Robot Gunner" You can get them pretty cheap. I found 3 at $5 USD each with free shipping. Make sure to shop around outside Amazon and such.
They are obvious knock offs of the Japanese version of Starship Troopers:
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I intend to repaint mine…although the current paint job is very clean. Decals and weathering will go a long way. I have a bad history with poly-resin as the stuff is brittle. They are definitely going on a base. The same manufacturer cranks out two other robots which are a bit more retro:
Here is the "Astronaut Tank Figurine"
…and the Astronaut Warror Figurine:
I don't expect the ammo belts on the latter will live long :) Any of these three would be right at home on a retro scifi battlefield.