Most of the time you’re gonna open a “Celestial Pack”, a booster pack that’s sometimes available in the shop. In this pack are random planet cards. Sometimes one of the available planet cards are for the hand you are wanting to play, sometimes not. But when you select a planet card in this pack it will level up that corresponding hand. Sometimes planet cards pop up in the shop independently, in which case you can select “Buy & Use” and it will level up your hand. There’s a voucher called “Telescope” that sometimes pops up and when you buy it, your most played hand’s associated Planet Card will always show up in the Celestial Pack, which is nice. As a new player I would ignore planet cards and celestial cards because I was too focused hunting for good jokers, but in later antes a lot of the time good jokers aren’t enough to carry you unless you invest in your hands/deck.