Any damage done to Dewgong by attacks from your opponent's Pokémon that has δ on its card is reduced by 40 (after applying Weakness and Resistance).

Ice Beam

20

Flip a coin. If heads, the Defending Pokémon is now Paralyzed.

Surge

40+

If Dewgong has at least 2 Water Energy attached to it, this attack does 40 damage plus 20 more damage.