PSA 10: PriceCharting; refreshed Sep 10, 2026
GemDelta shows Tropical Tidal Wave (Promo #HGSS18) at $1,400 market price (TCGplayer market). Its Delta multiple is 2.73x.
A PSA 10 Tropical Tidal Wave (Promo #HGSS18) is currently shown at $1,775. GemDelta labels this as an unverified PriceCharting guide fallback rather than verified recent sales.