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I like your idea. It's a lot more specific than the idea I made about 2 weeks ago, which involved screech and shadow tag abuse, and I can see it having a excellent effect on the metagame. I hope your idea does well.
Concept: "Stat-Lowering Terror"
Description: A pokemon that can use stat-lowering moves to terrifying effect.
Justification: As of now, stat-lowering moves are beyond useless. This concept seeks to make stat-lowering moves more relevant through anything from abilities to movesets...
How exactly does concept posting for new CAP projects work? Are more active members more likely to get an idea passed through? If the idea is not chosen, can you submit it again? I have an idea, and I'm wondering if I should submit it for the next project or polish it more.