**Trader consensus on the Polymarket for the Phantasmal Flames Booster Box price moving down by August 31 sits at a 75.5% implied probability, driven by the set’s established post-release price trajectory.** Released in November 2025 as the first expansion in the Mega Evolution era, the booster box saw strong initial demand and early secondary-market spikes above $400. However, prices have steadily eroded since, falling from roughly $460 in June 2026 to around $386 on major platforms like TCGplayer and PriceCharting as of mid-August. This reflects classic sealed-product dynamics: rising secondary supply from opened product and distributor allocations, alongside softening collector and investor interest once the hype cycle cools. No major catalysts—such as strong tournament play, new pull-rate data, or fresh reprints—are scheduled before the end of the month that would reverse the downward momentum. Historical patterns for Pokémon TCG sets show similar gradual declines in the 6–12 months post-launch absent sustained demand spikes. Traders are pricing in continued erosion through the end of August based on these observable supply-and-demand trends rather than any sudden reversal.