Hmmm, I did realize that The flying side would be weak to rock, forgot about the bug side. In fairness though, I think only Onix has a rock attack, and only one, so risky but not horribly stupid. Her speed and confusion being able to bypass the rock resistance really made her the only good back-up. But in the end, Poseidon with Bubble handled it well.
And...Why would Onix be double weak to water? It's a pure rock type, it should only have x2 vs water, not the x4 of rock/ground.
I'm actually not sure what gym type I would pick myself. Probably Steel type or water. Or normal.
Onyx is rock/ground. Steelix is steel/ground.
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