>>724662574
Every assassin can easily take down one or more basic space marines in direct combat (lore wise) and out right devastating in their niches. Like, its not even close unless plot armor is involved.
The only people that actually believes space marines are anywhere near an imperial assassin are coping while buying the newest Primaris model.

With that I will once again shill Assassinorum Kingmaker, best 40k book imo and a damn good book in general
>3 Autistic Assassins are dumped on a knight world and told to kill the king, who never leaves his mini titan
>proceeds to shit talk each other the entire time