When discussing the war, very often acts of war are labeled crimes. And I have to say, I get sick of it. I understand that the world we play in isn't really comparable to our world. That's the thing with fantasy settings and fiction in general. It's fictional.
But yet, things like the attack on teldrassil are called to be warcrimes because it targeted civilians. But in the context of the world, killing civilians is not a thing. It is not who you killed, but how many. When the roman Legions under Varus where killed by germanic tribes, it was horrific for the romans. It didn't matter if it were soldiers or noncombatants. The sheer number of man killed made it so terrible.
In medieval times, noncombatants were vital for the function of armies. Targeting civilians - to use the modern term - was a valid tactic to deny supplies and support for the enemy.
If you like, read here: http://www.oxfordbibliographies.com/...91279-0033.xml
But please, stop call everything a warcrime, just because noncombatants were targeted.