According to @CoinMarketCap, heavy Q2 2025 accumulation propelled a Q3 breakout above the Altseason Index 75 threshold, marking a brief Altcoin Season, source: CoinMarketCap on X, Dec 11, 2025. A tariff-driven liquidity unwind and ETF outflows then triggered a sharp reversal, collapsing the Alt Szn Index to roughly 19 by year-end and flipping conditions back to full Bitcoin Season, source: CoinMarketCap on X, Dec 11, 2025. Traders should tilt exposure toward BTC and monitor ETF net flows and tariff headlines for timing given the reported regime shift, source: CoinMarketCap on X, Dec 11, 2025.