Shadow Claw lets you discard a card from your opponents hand
Harpie Harpist is a great LVL4 monster with 1700 ATK/600 DEF, and when its Summoned you can target one of your Winged Beast monsters, plus one of your opponents monsters, and return them to the hand
There may be a situation where youre opening a Charizard pack, but the card youre looking for is in the Mewtwo pack
A particular card featuring fan-favourite creature Pikachu sells for over $1,000 Cdn on places such as eBay, which had people buying up as many packs as they could from hobby shops and big box stores
However, it is limited, and with no Magician of Faith, it can be a chore to get it back, so if you plan on running this card, be careful when you use it (But most often its a dead draw)