Hi For me Omnistone is useless rune. You can't control what u get. I have simple solucion. Omnistone + Precision give you (Press the Attack/Lethal Tempo/Fleet Footwork/Conqueror) Omnistone + Domination give you (Electrocute/Predator/Dark Harvest/Hail of Blades) Omnistone + Sorcery give you (Summon Aery/Arcane Comet/Phase Rush) Omnistone + Resolve give you (Grasp of the Undying/Aftershock/Guardian) [slayer-jinx-wink]
It doesn't matter that you can't control it. The cooldown is way shorter than what the keystones would be normally. If you can consistently proc them, you generate a ton of value that gives you an advantage over your enemy, regardless of what you pull.
For me Omnistone is useless rune.
It's like saying that lethal tempo is useless on mages (excluding azir XD) You're not meant to use it on pyke, you're meant to use it on champions that can use many keystones effectively (most importantly grasp of the undying, electrocute and press the attack must be easy to proc) So Quinn, Kennen, and any ranged vs melee would want omnistone (including corki mid vs melee) and eventually get predator in a shorter time frame than usual, since predator can be used for chunking people, roaming, returning to lane (not optimal but possible) and more. It's unfortunate that spellbook can't be used with omnistone though.
