As long as any Stadium card with Holon in its name is in play, each of your Pokémon that has δ on its card does 10 more damage to the Defending Pokémon (before applying Weakness and Resistance).
Attacks
20Hyper Beam
Flip a coin. If heads, discard an Energy card attached to the Defending Pokémon.
80Heavy Impact
How much is Gyarados δ #8/110 worth?
As of November 5, 2026, Gyarados δ #8/110 from Holon Phantoms sells for around $316.32 in raw, ungraded condition. Across the 2 printings we track, copies run anywhere from $341.31 to $2,000.00 depending on the version you're holding.
Grading changes the math on this one: a PSA 10 is valued around $8,534.49, roughly 27.0x the raw price, while a PSA 9 sits near $1,573.26. 1,678 copies have been graded to date, and 5% of them came back a 10 — worth knowing before you pay grading fees.
These figures come from nightly market-data syncs verified against completed sales. Use the chart above to see the trend before you buy or sell.