AoS Chips with faces

I just bought the new stormforged book so I could have the updated list for my girlfriends army (and a bunch of other stuff) which came with a bunch of chips that you can put next to models or terrain to indicate that they are currently under a certain effect. E.g. to show terrain is arcane.

Now most of them are selfexplanatory, but some of these chips only have the face/helmet of a stormforged on them, what in the world are these for? Anyone have any ideas?

 

This is what they look like.

 

Looks like hero faces, so it may be to show a unit has been buffed by this leader.

 

buffed by it's leader? I haven't gone through the entire book yet since I've only had it for a day or so, did I miss a rule? Don't leaders usually only have 1 extra attack or some such effect?

 

Ah. I was thinking of this...

 

I meant if Lord Castellant had used his warding lantern on a stormcast unit or something, you could mark that unit with the marker that looks like him. I could be wrong, but that's what they look like to me.

 

That's not particularly heroic and stormforged-ish though

@Bowser right makes some sense I suppose