Abilities » Plasma Bane | Trainers » Pokemon League Headquarters | Attacks » Trifrost
If my opponent has a card with "Colress" in its name in their Discard Pile and Pokemon League Headquarters is in play, can I use Kyurem's "Trifrost" attack with only one energy attached due to its "Plasma Bane" Ability?
Kyurem's Plasma Bane ability sets Trifrost's attack cost to one. Since the attack cost has been set to a specific number, Pokemon League Headquarters does not add to it.
Source: TPCi Rules Team (2024-09-12)
Attacks » Grasping Draw | Trainers » Pokemon League Headquarters
If Pokemon League Headquarters stadium is in play, how many energy are needed for energyless attacks like Cleffa's "Grasping Draw" attack?
Any attacks that normally cost no energy now require at least one energy to be attached when Pokemon League Headquarters is in play. However, if an effect like Cramorant's "Lost Provisions" Ability sets an attack's cost to zero energy, Pokemon League Headquarters does not add an additional energy requirement to it.
Source: TPCi Rules Team (2024-07-11)
Abilities » New Moon | Trainers » Pokemon League Headquarters
If Pokemon League Headquarters is in play and I have Lunatone with the "New Moon" Ability and also Solrock in play, do my Basic Pokemon have an extra {C} cost to their Attacks?
No, but your opponent's Pokemon do.
Source: Obsidian Flames FAQ; TPCi Rules Team (2023-08-10)