Can you use an Imperial Guardsmen in a Space Marine army?

I started a Warhammer 40k Space Marine army and painted the figures,but then I saw an Inquisition Witch Hunter and now I wanna use one in my army.Can I do that?Can you use an Imperial Guardsmen in a Space Marine army?
Though this is the wrong category for this question, I'll answer it briefly - You can use an Inquisitor with Space Marines if you follow the rules as set forth in the Witch Hunters or Daemon Hunters codex. It would fall under the category of 'allied troops.' There are rumors floating around of a new and improved Inquisition codex coming out, but nothing concrete has been revealed yet. Your only other alternative is to gather at least 3000 points and put everything down in an Apocalypse battle, since you can field nearly everything you own in that respect.



If you're just using the Space Marine codex, then no.Can you use an Imperial Guardsmen in a Space Marine army?
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