We should avoid making runes that specifically act as hard counters to certain abilities that make champions worth playing. Nor does it add anything to the theme as a hole with its stand alone abilities.
I agree that the specific interaction with Seism isn't something that should be made into a real rune. Solution is probably to make it 30 nora, 21 hp, and give it one more minor ability. I have no idea what you mean about "add something to the theme."