Father Illearth/Lord of Banefire - why?

[Zurai]

Having just completed a very long game with Caelum on the Kingdom of Karan map (very nice map by the way Targa!) in which I summoned all of the elemental royalty, I have to wonder what the point of these two is. Neither one has a special ability (other than Anthrax's slightly improved fire shield), they have decent magic but nothing exceptional, and they require paths that don't combo that well.

Is there some little facet that I'm missing here? I'm NOT saying they're useless, just that I personally can't see why you would summon either one specifically instead of expending a little more effort to get the regular Earth or Fire Kings, who can summon friends every turn.