Beings of Tash Kalar
All lone riders in the game so far (Knight, Wolf Rider and even Centaur Spearman) have an L-shaped pattern. The Gryphon Rider is no exception; his shape is just a diagonal L. Also, with a bit of imagination, you can see the prancing gryphon in the pattern, with the rider summoned right behind his neck.
It is obvious: The gryphon rises to the clouds and then dive attacks any square of the arena. Then you may keep it as one heroic piece or dismount the rider from the gryphon and thus get two common pieces, the rider next to his gryphon. It is not written on the card that this option represents dismounting, but I am pleased that many players recognized that. :)
In a deathmatch, you may go for a double kill (by summoning and by the leap). But generally, this card is very useful mostly in the High Form, both when fighting for certain spots (you kill an enemy heroic piece and install your own heroic piece on a space) or for tasks that require lots of pieces (connecting, encircling etc.). When you go for a chain, you may shape part of the chain as a Gryphon Rider – then you may summon the Gryphon Rider and, with one action, fill in the last two missing pieces of the chain.
I suspect the visual concept of a dive attack might be inspired by the gryphon in Heroes of Might Magic V. :)
The strength of this card changed back and forth as we were balancing the decks. At one moment, it had exactly the same effect as Eagle Lord, but we didn't like that fact. During balancing we realized the Empire needed to be strengthened a bit in the High Form (but not in deathmatches) and thus I added this option that is mainly useable in the High Form. I think it remained as the final version because we really liked the theme of it. :)