He talked also about "that mage that does 4 damage to all allies", so there's a mistake somewhere.
However, I think that GDC got the right one...

Terrifying?
With 4SE to trigger the ability and a 6cc ally (because, who would lose haste and ambush with skull if not in desperate cases?) that would be terrific...

Well, I can only applaude your post, Raphael.
Totally agree with every single word.
Well done.