The nature of CCGs means that the cards in the packs are entirely random across the set rarity of each pack, which for each Lorcana booster pack is 6 common cards, 3 uncommon cards, 2 rare, super rare, or legendary cards, and 1 foil card (random rarity level)
Lay Down Arms is more restrictive than its counterparts
You need to have already declared an attack with it, so it has 10,000 Attack Power
This mechanic represents Sins various regenerative capabilities, the creation of Sinspawn, and also shows the mysterious cycle that the people of Spira are trapped in
I do appreciate how broad it is, but hopefully you can just play Sephiroth's Intervention or Fate of the Sun-Cryst instead
[18] As you get more familiar with the Lorcana rules, start using booster packs to get new cards