This has a tonne of utility in all phases of the game
for a turn 1 search, and it can trigger cards like Loading
Once per Chain, when a Zombie monster, except "Doomking Balerdroch", activates its effect (except during the Damage Step) (Quick Effect): You can apply 1 of these effects (but you cannot apply that same effect of "Doomking Balerdroch" again this turn)
The final secret mission is called Champion of the Sinnoh Region and is awarded for collecting the full art Cynthia card alongside 1 Star cards of her four key Pokmon: Gastrodon, Lucario, Spiritomb, and Garchomp
The move that costs 1 Lightning energy, called Flash Search, allows Mew's trainer to look at the top 3 cards of their deck and place 1 in their hand before returning the other 2 and shuffling the deck
Skullclamp is a staple of Token decks, as most are going to be 1/1s, allowing you to easily draw out a lot of cards from your deck to get to your win conditions