You can't have more than 1 cards with the same name in your deck. If a card would go in the discard pile, put it in the Lost Zone instead.
You can only have 1 Prism Star Card of the same name per Deck
Dance of the Ancients
Once during your turn (before your attack), if this Pokémon is on your benchyou may choose 2 of your Benched Pokémon and attach a Energy card from your discard pile to each of them. If you do, discard all cards from this Pokémon and put it in the Lost Zone