Ogre's, +10 Morale?
 

So I picked up some ogres, and randomly in a battle I pulled up their info page and noticed the smiley face had a huge grin, so I hovered over it and it said '+10: Anticipates Trophies'. Any idea what this is from?

Any orc unit that gets a kill (finishes off a stack) gets this morale boost. Considering how much stronger they get when it triggers, it behooves you to often finish off a stack, even if it is less efficient.