Thought this might clear some things up. i copied it from the wizards of the coast Compendium.
== METRONOME (Clefairy - Base Set, Clefable - Jungle Expansion)
Q. Please explain Metronoming attacks where the attack mentions the specific name of the opponent’s Pokémon.
A. Anytime an attack is self referencing (meaning it mentions itself) and you copy that attack with Metronome or Ditto, you replace the self-referenced name with the name of the Clefable/Clefairy/Ditto, etc. (Dec 14, 2000 WotC Chat, Q66)
Q. Can Clefable copy Pokémon Powers?
A. No, only attacks. (Jul 6, 2000 WotC Chat, Q264)
Q. How does Metronoming attacks like Meditate, Water Gun, Hydro Pump work? Do you copy the base damage or do the effect too?
A. Metronome copies the base damage; you would need additional Energy on Clefairy/Clefable to do additional damage with those copied attacks. (Jan 27 WotC Chat)
Q. Suppose Clefairy uses Metronome to copy Chansey’s Double-edge attack (which does 80 damage and has the text “Chansey does 80 damage to itself”). Does that mean Clefairy does 80 damage to Chansey plus Chansey does 80 damage to itself, for a total of 160 damage to Chansey?
A. No, Clefairy will do 80 damage to Chansey and Clefairy will do 80 damage to itself. In general, if Pokémon A copies an attack from Pokémon B, any copies of Pokémon B’s name in Pokémon B’s attack should be replaced by Pokémon A’s name. (Think of Pokémon A’s name, when written on Pokémon A’s card, as really being “this Pokémon.”) (Base Set WotC FAQ)
Q. If there is a Clefable and a Ditto active, and the Clefable has one Energy can he Metronome, and do the Ditto’s Minimize attack, which is really his own, without having the two Energy required?
A. Yes, he could, since he would be Metronoming the Clefable’d Ditto’s Minimize attack. (2-17-00 & 6-30-00 WotC Chat)
Q. How much damage would Metronome do when the damage of the attack copied is dependent on the amount of Energy discarded?
A. Ok. Here we go: the Metronome attack copies the attack and negates the cost (a.k.a. the Energy cost of the attack). It also negates any payments to complete the attack like Charizard’s Fire Spin where it says you have to discard Energy in order to do this attack. However on cards like Blastoise and any other card that has any added attack bonus for extra Energy or attached cards you have to follow those rules as normal. Example: if Clefable copied Hydro Pump he would do 40 points of damage unless he had extra Water Energy on him, the same holds true for discarding for extra effects. (Feb 24 WotC Chat)
Q. When Clefable Metronomes Big Eggsplosion how much damage does it do… and what is needed?
A. You would flip a coin for each Energy card attached to CLEFABLE (not Exeggutor). For each heads that comes up it would do 20 damage. (Mar 2, 6-22-00 Q37 WotC Chat)
Q. If I use Clefable’s Metronome copying Lapras’ Water Gun attack (Lapras having 3 Water on him)… how much would the attack do?
A. The base damage is 10; it would do 10 more for each additional Water Energy on CLEFABLE, not on Lapras. (Mar 2 WotC Chat)
Q. So to Clarify, Clefable with any 3 energy could do the “extra” damage in a Hydro Pump? They would not have to be water energy?
A. Nope! You could use any kind of energy to pay for the metronome attack, THEN energy PAST that would have to be water energy to do the extra Water Pump damage. (April 6, 2000 WotC Chat Q74)
Whenever Metronome is used to copy an attack that “refers to itself” like Chansey’s Double Edge, (does 80 to defending Pokémon AND does 80 damage to Chansey), you would replace the self reference with Clefable or Clefairy. So the attack would read "does 80 damage to defending Pokémon and 80 damage to itself (i.e., Clefable or Clefairy). If an attack does refer to other Pokémon, like Bellsprout’s Call for Family attack (Search your deck for a Basic Pokémon named Bellsprout and put it onto your Bench), you would NOT replace the reference with Clefable or Clefairy. So if you used Metronome to copy this attack, you could only search your deck for Bellsprouts. (Mar 2 WotC Chat)
A ruling on Metronome and Dark Charmeleon (available in Top Deck #6). Metronome states that it copies that attack except for Energy costs and anything else required IN ORDER TO use that attack. The important part of this text is the IN ORDER TO part. This means that Metronome ignores anything listed in an attack’s requirements but ONLY if it has the words IN ORDER TO in its text (such as Charizard’s Fire Spin). If the words IN ORDER TO are NOT part of the text then Metronome does NOT ignore it. So, in the case of Dark Charmeleon’s Fireball text (Use this attack only if there any Fire Energy cards attached to Dark Charmeleon), Metronome does NOT ignore this condition. This attack was specifically worded this way so that Metronome couldn’t copy it without the Clefable/Clefairy actually having Fire Energy on it. There will be other cards in the future that will use this same sort of wording to make it hard for Metronome to copy it. (Apr 13, 6-1-00 Q62 WotC Chat)
Q. I heard that in order for Clefairy or Clefable to Metronome Moltres Wildfire you need to discard the Energy off of Clefairy/fable still, even through Metronome says not to discard Energy. Why?
A. Metronome says you do not have to discard Energy that is REQUIRED to do the attack; the EFFECT of the Wildfire requires you to discard Energy, not the attack. (Mar 9 WotC Chat)
Q. When your opponent has Moltres and you use Metronome for Wildfire how would you go about that?
A. Well, you only need to pay 1 Colorless to Metronome the Wildfire but it won’t do anything unless you pay the normal EFFECT cost of discarding an Energy card [Ed. Note: Fire Energy card] for each card you want the opponent to discard. (Mar 9 WotC Chat)
Q. If Clefairy or Clefable copies Moltres’ Wildfire, does she still have to discard Fire cards to use it?
A. Yes. The discarding is NOT a cost of the attack but affects the result of the attack. (Mar 30 WotC Chat)
Q. If Clefable can use Metronome, does it have to discard while it Metronomes attacks that need to discard, such as Charizard’s Fire Spin?
A. If the discarding is required like for Fire Spin you do NOT, if it is optional like Moltres’ Wildfire, then you DO. (Mar 16 WotC Chat)
Q. If you Metronome Haunter’s “Dream Eater” does the Defending Pokémon have to be Asleep or not to work?
A. Yes, it does. (Mar 2 WotC Chat)
Q. How would it go if it Metronome’d Swords Dance? Next turn, would it will deal twice as much according to the Japanese Text? Or would it state in the US Text.
A. You would have to Metronome the Sword Dance the first turn and then Metronome the Slash the next and it would be doubled for your Clefable. (Mar 2 WotC Chat)
Q. If Clefable has 1 Fire Energy attached, and is opposite a Dark Charizard, does Continuous Fireball and flips heads, must the Fire Energy be discarded?
A. Yup, it is NOT a requirement to do the attack so it is NOT ignored by Metronome. You’ll have to flip coins equal to the number of Fire Energy cards attached to Clefairy if you copy it though. This is NOT a requirement but an effect of the attack so Metronome does NOT ignore it. (May 4, 2000 WotC Chat, Q7; May 18, 2000 WotC Chat, Q11; June 15, 2000 WotC Chat, Q49)
Q. Clefable CAN use MP Moltres’s Hyper Flame if the Clefable had a Fire energy, right? What about a Rainbow energy?
A. That would work too. (Aug 3 2000 WotC Chat, Q113)
Q. There is a new clause in the NEO Genesis Theme Decks that states a Pokémon must evolve into something with it’s name in the upper left corner. But this conflicts with your rulings that Clefable can evolve into a Gyarados. Now who is right, your ruling or the NEO Rule Book?
A. Correct, this gets rid of that problem. (Jan 4, 2001 WotC Chat, Q53)
Q. Okay, thanks for the ruling on Ditto and Rapid Evolution. However, what about Metronoming the attack? What would happen? Anything?
A. That won’t work either. Gyarados and Dark Gyarados must be placed on Magikarp only, not a Clefairy/Clefable. (May 4, 2000 WotC Chat, Q34)
Q. If you Metronome “Giant Growth”, does your Clefairy/fable become 80 HP and whenever they metronome “Pound”, it goes for 30 damage (until they are benched, evolved, etc.)?
A. Yes, if you flip heads… (May 17, 2001 WotC Chat, Q49)
Q. How much damage would Dark Weezing take if Clefable/Clefairy Metronomes the attack?
A. 20 damage for each Weezing, Koffing, and Dark Weezing in play, as usual. (May 4, 2000 WotC Chat, Q59)
Q. Also, If a Clefable metronomes a Mewtwo, will Barrier work?
A. Yes (April 20, 2000 WotC Chat Q88)
Q. If a Clefable metronomes Arcanine’s Takedown, Does Clefable do 30 damage to itself?
A. Yup! (April 20, 2000 WotC Chat Q91)
Q. If Clefable is opposite Brock’s Ninetales with Wigglytuff attached, can Clefable Metronome “Do the Wave” or only “Will-o’-the-Wisp”?
A. No they could only use the attacks of the attached card on the Brock’s Ninetales. (Oct 26, 2000 WotC Chat, Q1 & Q44)
Q. If a Clefable uses Metronome and it copys TR Zapdos’ Electroburn does it take any damage if it has 0 lightning energies on it?
A. Right-o [Ed.Note: No, it does not take any damage]. (Oct 26, 2000 WotC Chat, Q15)
Q. If my opponent has a Clefable active, I have a Misty’s Staryu active, and the Clefable uses Star Boomerang [via Metronome], does my opponent have to flip (he has the Clefable)? If its heads, does the Clefable go back to his hand?
A. Yes it does (it is a self referencing attack and you replace Misty’s Staryu with Clefable). Either way damage is done before you shuffle Clefable and all attached cards back [into your hand]. (Nov 30, 2000 WotC Chat, Q29)
Q. Suppose a face-down card is active (via “Lt. Surge’s Secret Plan”), and opposite Clefable which then attacks with Metronome. The card is then flipped over and it’s not a basic Pokémon; does Metronome get to use the next active’s attack or not?
A. Yes it does, just by announcing you will use Metronome, you must flip over the face down card. If it is discarded you MUST choose an attack off of the next active Pokémon for Metronome. You CANNOT decide NOT to use Metronome as you already stated that choice. It is just clarifying exactly what you are Metronoming. (Dec 7, 2000 WotC Chat, Q24)
Q. If you use Metronome on Sabrina’s Alakazam’s Mega Burn, can you not use Metronome, not use Mega Burn, not use a Metronome of Mega Burn, or none of/multiple of the above?
A. You can’t use this attack [Mega Burn] during a turn after you used it. Even Metronoming it is the same thing and you CAN’T do that. You can Metronome a different attack though. (Dec 7, 2000 WotC Chat, Q167)
Q. Defender has Sabrina’s Alakazam active, other Psychic Pokémon on bench. Attacker has Clefable active. Can attacker Metronome through Psylink to use the defender’s benched Pokémon attacks, as Sabrina’s Alakazam’s power says Sabrina’s Alakazam has a copy of all it’s benched Pokémon’s attacks? But, Clefable can’t use the attacker’s benched Pokémon’s attacks because Clefable doesn’t have the Psylink power?
A. Yes, as long as Sabrina’s Alakazam’s Power is working. You can Metronome only attacks that Sabrina’s Alakazam has. Since it has a copy of all Psychic attacks when Psylink is active, you can Metronome these. (May 10, 2001 WotC Chat, Q69 & Q80 & Q140)
Q. Say Clefable is facing a Sabrina’s Ghastly(30HP). Clefable Metronomes the Ghastly’s “Fade Out”. Does Clefable stay in play or does Clefable and the energy return to your hand? Does Clefairy go to the Discard pile?
A. This is a self-referencing attack. Replace Sabrina’s Gastly with Clefable and do what the attack states. Clefable and all [energy] cards attached to it will be returned to your hand. [Ed.Note: We presume this means that Clefairy does indeed go to the discard pile since it is not an energy card]. (Jan 4, 2001 WotC Chat, Q86)
Q. If you use Clefable’s Metronome Attack to copy Lugia’s Elemental Blast, do you have to discard a Fire, a Water and an Electric Energy, since the Attack specifically states you need to discard those cards.
A. You do not, as Metronome ignores all “IN ORDER TO” statements in an attack, which is what is written on Lugia. (Jan 18, 2001 WotC Chat, Q32a)
Q. If Clefable Metronomes Lugia’s Elemental Blast, it can’t use it unless it can discard a R, W, and L energy, right?
A. Nope, it ignores any ‘In Order to…’ text. (Mar 8, 2001 WotC Chat, Q111)