Characters cannot be used on the turn they're played because, as the Lorcana rulebook says, "You need to wait for their ink to dry!" After waiting one turn, your now dry characters are free to challenge opposing characters in an attempt to deal enough damage to send them to the discard pile
Despite Amber/Emeralds impressive range of cards, the other Into the Inklands starter deck has many things going for it that Amber/Emerald doesnt, including a more cohesive strategy and a healthy reliance on location cards
Having a consistent way to not only create a second combat phase but also untap all the creatures you control for a measly four mana is a phenomenal pairing, especially when used as a Commander to bring her back into the fight after being targetted
As the name suggests, you should start here and not worry about anything else until you know whether you enjoy and want to get more serious about playing the game or collecting the cards
Its a great way to revisit the seriess biggest moments while still getting a booster format built for actual play