Here's the thing -


This was found on http://heroes.ag.ru and has been repeatedly verified. ;)

The Ethereal is still the fastest demon, but I don't think this statement has much impact overall. I think the only downside of the Ethereal is its vulnerability to spells (they should have allowed positive effects to be applied to it; that would have made it even better). But in general, who said that only these creatures will fight in battle? And even if it sends the Phoenix and Dragon forward, the Dragon will be more effective in this case (more health, stronger defense). Yes, in this topic, we are determining the best fighter, the one most adaptable to many units, and not just a few (Ethereals are more adaptable to many fighters).
By the way, only a newbie would take magical dragons or dragongolems against Chaos (Titans have chaos resistance).