Three cards have been added to the list of errata for the Pokémon Trading Card Game. [...] The text below reflects what the card should say, not what was originally printed. "When you attach an Energy card from your hand to Onix, remove a damage counter from Onix." This Poké-Body only works when you attach an Energy card to Onix.
Source: PUI Rules Team (2010-05-06), TPCi Errata Update (2010-05-07)
Can I use Ninetales' "Roast Reveal" Poke-POWER when I have no cards in my deck?
Yes, you do as much of the power as you are able; discard 1 Fire Energy card from your hand, then the Poke-POWER's effect ends, without drawing any cards.
Source: HeartGold & SoulSilver FAQ (2010-02-11), PUI Rules Team (2010-02-11)
Can Typhlosion's "Afterburner" Poke-POWER be used if there is no Energy in the discard pile, just to place a damage counter on one of my Pokemon?
No. Since you can't attach an Energy from your discard pile to one of your Pokemon, you can't use the rest of the power.
Source: HeartGold & SoulSilver FAQ (2010-02-11), PUI Rules Team (2010-02-11)
If my opponent has less than 3 cards in his or her deck, so that I can't reorder the top 3 cards, can I still use Slowking's "Second Sight" Poke-POWER to look at the remaining cards in the deck?
Yes, you look at your opponent's remaining cards, then put them back in the deck in any order.
Source: HeartGold & SoulSilver FAQ (2010-02-11), PUI Rules Team (2010-02-11)
Can I use Shedinja's "Vessel of Life" Ability to attach it to a Pokemon that already has another Pokemon Tool card attached?
No, you cannot; the rulebook states "each Pokemon can have only 1 Pokemon Tool attached at any time". However, if there's an effect that overrides that rule, such as Genesect GX's "Double Drive" Ability, then you would be able to attach Shedinja to a Pokemon that already has another Pokemon Tool card attached.
Source: TPCi Rules Team (2018-12-27), TPCi Rules Team (2009-01-03)
If I intend to use a Poke-POWER [or Ability], do I have to announce its name or can I just take the action specified?
You have to clearly communicate your intent to use a Poke-POWER [or Ability] by some method other than just performing its game effect. Show or tell your opponent which Pokémon is going to use what Power.
Source: PUI Rules Team (2008-11-13)
If I use Caterpie's "Pupate" Poke-POWER to successfully evolve into Metapod, can I then immediately use Metapod's "Emerge" Poke-POWER to attempt to evolve into Butterfree, all on the same turn?
Yes, you can.
Source: PUI Rules Team (2008-02-21)
If my opponent has a Pokémon with only 2 damage counters on it, can I still use Absol-EX's "Cursed Eyes" Poké-POWER on it?
Yes, you can. If you use this power, you move the 2 damage counters to another one of your opponent's Pokémon.
Source: Power Keepers FAQ (2007-02-01), PUI Rules Team (2007-02-01)
If my opponent has more than one Pokémon with damage on it, can I use Absol-EX's "Cursed Eyes" Poké-POWER on one that has less than 3 damage counters even if they have another Pokémon with 3 or more damage counters on it?
You may choose to use Absol-EX's power against any Pokémon with damage counters, but if it has less than three you would move all of the damage counters off of it.
Source: PUI Rules Team (2007-02-01)
When using Absol-EX's "Cursed Eyes", do I have to move all three counters or can I choose to move less than three (like if I only need to move one counter to KO another Pokémon and wished to leave the other two where they are)?
You must move 3 from that Pokémon if there are 3 that can be moved.
Source: Power Keepers FAQ (2007-02-01), PUI Rules Team (2007-02-01)