Sorry for quadruple posts but i couldn't resist (resisting is not my strongest virtue ) DT tyranid style .
I have been reading a book about a mechanicus explorator fleet searching for ancient tech in the far reaches of the galaxy, assisted by a squad of Black Templars, a full cadian regiment, and a butt load of skitarri, combat servitors and bad-ass techpriests. (Called Priests of Mars, Lords of Mars, Gods of Mars). The Black Templars are pretty awesome in this book and always leading some suicide charge and winning or fighting hordes of hostiles behind enemy lines. Thought this was a good depiction of one of there many "last" stands