I wonder how relevant the rush is. Otherwise it's the same infinite end-game finisher as the spellstone, that only saw experimentation for a week after the moment it got released. Not too optimistic it going to make it.
I like the effect but at 8 mana it will be difficult to play it effectively. Another core problem might be that there are just a couple of rush cards that are good enough to run independent of this effect. This way you always have to balance the risk of running bad rush minions against the risk of drawing all of them before you can play this on turn 8. If the wording was „discover a minion with rush“ the card would be waaay better and maybe even be worth the price.