>>6817200>I believe it actually comes with the body.Unless the previous owner already dissassembled a Mazinger SoC and added the Gekiganger pieces, that's not going to be the case.
The pic you posted comes from from Wotafa's review. He actually talks about having to use a Mazinger as the base, and you can also see the instruction manual at where it shows the Mazinger figure. Pic related.
If it includes the Mazinger pieces or it's already assembled, then no problem. If not you will have to track a SoC Mazinger. Either way I hope you enjoy your Gekiganger 3 anon, I wish they made an actual SoC of it.