I am looking for the name of a fantasy novel, the details of which I only faintly recall from reading a different worldbuilding exchange thread. I think that thread was something like "how a war could suddenly end as soon as it started?"
One answer referred to a particular war in A Song of Ice and Fire which was considered 'over' as soon as the leader of one side was killed. Then all the opposing troops retreated. Their war was a vendetta against a single man rather than against a nation.
(If anyone has details about the ASOIAF reference I can run a search for the original thread. . . . )
Another (or maybe the same) answer mentioned these giants. They have a natural hatred of war but when it cannot be avoided undergo some sort of bodily transformation that makes them better at fighting, and this shows how committed to it they are. I don't know if the transformation is reversible or how it would explain a war suddenly ending. Perhaps the transformation is ultimately fatal so all combatants die and this is what makes the war suddenly end?
Edit: To clarify I am looking for the name of the novel in question -- the one about the transforming giants. Has anyone heard of a novel like that?