Trainers » Earthen Seal Stone | Abilities » Fighting Instinct | Meta-Rulings » Meta-Rulings
Any effect that alters the cost of a Pokemon's attacks is intended to alter the cost of ANY attack that Pokemon uses, not just the ones printed on the card. This means any attack that the Pokemon is given access to, such as Earthen Seal Stone's "Star Gravity" attack when attached as a tool, can be used at the altered cost when effects such as Galarian Zapdos V's "Fighting Instinct" Ability are in play. For example, Fighting Instinct says, "This Pokemon's attacks cost {C} less for each of your opponent's Pokemon V in play"; however a more accurate description would be, "Attacks that this Pokemon uses cost {C} less for each of your opponent's Pokemon V in play." This applies to effects that reduce or increase attack costs, and goes all the way back to the Black & White series thru current series.
Source: TPCi Rules Team (2022-12-01)
Meta-Rulings » Meta-Rulings
Effects of Poke-Powers, Poke-Bodies, and Abilities do not end when a Pokemon is moved from Active to Bench and vice-versa.
Source: PUI Rules Team (2009-02-26); TPCi Rules Team (2021-05-13)
Meta-Rulings » Meta-Rulings
Prior to the "Black & White" series, when a Pokemon refers to itself by name, interpret that card as though the text reads "this Pokemon". This has the practical effect of not including other Pokemon of the same name; if a Pokemon copies that text, it refers to itself, not the original Pokemon. Beginning with "Black & White", when a Pokemon refers to itself by name, this extends to other Pokemon of the same name; if a Pokemon copies that text, it refers to other Pokemon of the same name. Also, when a Pokemon refers to "this Pokemon", this has the practical effect of not including other Pokemon of the same name; if a Pokemon copies that text it refers to itself, not the original Pokemon.
Source: PUI Rules Team (2008-04-17), TPCi Rules Team (2019-05-16)
Meta-Rulings » Meta-Rulings
You cannot have more than 6 Pokemon in play, including Active and Benched Pokemon, unless the card specifically allows for it (e.g. Sky Field).
Source: PUI Rules Team (2008-01-31), TPCi Rules Team (2018-07-26)
Meta-Rulings » Meta-Rulings
Attacks and Abilities on a Pokémon that refers to itself now use the phrase "This Pokémon" instead of the name of that Pokémon. This should clear up confusion during any situation where Abilities can be copied.
Source: TPCi Rules Team (2011-12-01)
Meta-Rulings » Meta-Rulings
Effects that prevent you from healing or from removing damage counters do not affect moving those damage counters between Pokémon.
Source: TPCi Rules Team (2011-12-01)
Meta-Rulings » Meta-Rulings
Whether a card's effect is optional or not is determined from the card text. If there is no explicit indication that you have a choice, then you don't have one and the effect is mandatory.
Source: PUI Rules Team (2011-09-29)
Meta-Rulings » Meta-Rulings
You cannot play a card if it is public knowledge that it will have no game effect. Paying a cost does not satisfy the requirement that the card has a game effect.
Source: PUI Rules Team (2008-01-31), PUI Rules Team (2009-03-12)