Cornerstone Mask vs Milotic?

The_Mo9

So Milotic has an ability that prevents all damage from and effects of attacks done by Tera Pokemon to it, and Cornerstone mask Ogerpon is a Tera Pokémon, but its attack has an effect that ignores all effects on the opposing Pokémon. This means that Ogerpon’s Demolish attack ignores Milotic’s Sparkling Scales Ability, while Sparlking Scales also ignores the effect of Demolish. So, does Ogerpon do damage to Milotic in that situation?

OlderAngel11

I don't believe that Cornerstone mask's attack condition is an effect of the attack. So it should hit through the ability.

The_Mo9

Thank you