Griffen Mount

[Glix]

Griffin Mount 
Creature – Griffin Equipment.
Flying
~this~ may be equipped as if it wasn’t a creature.
Equip 
Equipped creature gets +0/+1 and gains flying and first strike.
~this~ and equipped creature must attack and block together.

I'm not sure if I've got the wording correct, but the basic idea is a top down design of what the card is.

[Pave]

Does it have a power and toughness?

And is a lot to spend for the proposed effect.

[Titanium Dragon]

Beyond not working, why not just...

Griffin Mount
Creature - Griffin
Flying, banding
Creatures banded with Griffin Mount gain flying and first strike until end of turn.

[parallax]

It should probably be
Griffin Mount

Creature -- Griffin
2/2
Flying
  : ~This~ becomes an equipment artifact with "Equipped creature gets +0/+1 and gains flying and first strike." Attach ~this~ to target creature.

Unless you want it to remain a creature while equipped so it can still be Shocked, etc.

[Anusien]

Why not a creature with T: Target creature gains flying, first strike and gets +0/+1 until end of turn.

I know there were creatures created in that fashion during IA block, like Phantasmal Mount.

Phantasmal Mount {1U} |Creature -- Phantasm|  1/1. Flying / T: Target creature you control with toughness 2 or less gets +1/+1 and gains flying until end of turn. When Phantasmal Mount leaves play this turn, sacrifice that creature. When the creature leaves play this turn, sacrifice Phantasmal Mount.