Well, this is quite simple, as Pendulum Monsters that are on the field (including face-down or in the Pendulum Zones) go to the Extra Deck if they are sent from the field to the Graveyard
It's one of those cases where you have a favourite thing and you can't really say why it's your favourite
Each deck set includes 1 ready-to-play deck of 100 Magic cards (2 Traditional Foil Legendary cards, 98 nonfoil cards), a Collector Booster Sample Pack (contains 2 Traditional Foil or nonfoil special treatment cards, with 1 Extended-Art card of rarity Rare or higher and 1 alt-art, alt-frame card of rarity Uncommon or higher), 1 foil-etched Display Commander (a thick cardstock copy of the commander card with foil etched into the cards border and art), 10 double-sided tokens, 1 deck box (can hold 100 sleeved cards), 1 Life Wheel, 1 strategy insert, and 1 reference card
Storage Capacity: This case can hold up to 155 single-sleeved cards, including the 1 side loader that comes with the case