Being cards featuring Pikachu already makes these cards desirable for us all, but making them sparsely obtainable made it so anyone outside of China will have to pay a pretty penny to own any of them
The buyer still has to provide a card of the same rarity they either dont want or need, while the seller receives a card they can resell, repeating the process infinitely
Blackblade is similarly a great beater offering a bit of support to the attacks, a bit of extra utility and value, but mostly just a very hard to handle threat
Lastly they are pretty nasty to get countered and you really don't want to have to worry about your support stuff getting countered in a way that can ruin you
In general, also try to have four copies of each card you definitely want, so they come up more reliably
Pikachu - 25/25 - Holo - McDonald's 25th Anniversary Promo Out of stock