Warhammer 40,000

Most Space Marines have badass or threatening Battle Cries. Not the Lamenters chapter. For them, it's "For those we cherish, we die in glory", and they mean it. When the Lamenters launch a defensive action on a world under Tyranid assault, they won't nuke the planet and call it a day; they will save all three million people on the planet first, or die to the man trying.

Sadly this ending may be sooner than later.

(If anyone knows the author let me know so I can put it in the tags.)