Basically the way it works, as is printed on the card, is that you can cast it when you declare your attackers, turn your attacking creatures face-down and then shuffle them around
Once it hits zero, the card goes to the graveyard
While it is certainly a card for collectors to proudly display in a binder or slab, you can also factor in Pikachu exs competitive viability
For me, it's the online play that's where it's at - and that's also the core of why I've fallen a little ungracefully for Pokmon TCG Pocket despite my own initial reservations
It doesn't gain keyword abilities (unless those keyword abilities are activated), triggered abilities, or static abilities
Kaervek, the Punisher Kaervek, the Punisher turns your crime-committing instants into a Snapcaster Mage effect for your black cards with the additional cost of 2 life