Double sleeving cards are more popular in the card gaming scene, where cards are handled more heavily as they are shuffled and played with
Cardhoarder deck editor While it may seem simplistic, its intuitive interface makes it one of my preferred methods for tracking my collection on MTGO
Clean them gently (never alter or press), use penny sleeves and card savers, and double-box for safe shipping
If your opponent tries to remove a creature you control, you'll draw a card, and you can facilitate drawing an absurd number of cards by just targeting your own creatures
LIM AND NICO ROBIN
in addition, when the "pawn", "Angelechy Enlisted", crosses over to the opponent's field, it can "promote" by shuffling itself back into the Extra Deck and have a stronger "Angelechy" Synchro Monster take its place