Overcall is a trustless platform for a new asset class: skill-based markets, where trading and prediction markets meet. Every product is non-custodial and settles against one shared onchain vault, and the entire platform runs on a single token, $OVER. The vault takes the other side of every position instantly, so markets are always liquid with no order book to bootstrap. Pricing comes from decentralized oracles, the pricing model is pinned onchain, and every result can be independently recomputed, so nothing runs on trust. In the first product, Channels, users draw a price channel on a live chart and win if price holds it, in either direction; in Prediction, they take the other side of anyone's channel at the same probability-based odds, while creators earn royalties.