If I have Meganium with "Wild Growth" Ability on the bench and Teal Mask Ogrepon with 2 Basic Grass Energy attached in the Active Spot, can I use its "Myriad Leaf Shower" attack if Nighttime Mine Stadium is in play?
Yes, you can. Wild Growth counts the 2 Basic Grass energy cards as 4 energy, so you satisfy the new attack cost of 4 Energy due to the Nighttime Mine.
Source: Ascending Heroes FAQ; TPCi Rules Team (2026-01-22)
If I have Meganium with the "Wild Growth" Ability in play, does my Teal Mask Ogerpon ex's "Myriad Leaf Shower" attack do +90 or +180 more damage if there are only 3 basic {G} energy cards attached to it and no energy on the Defending Pokemon?
You get +180 more damage. When an effect counts "attached" energy you count the total amount of energy including the amount added by abilities like Wild Growth.
Source: TPCi Rules Team (2025-10-23)