LORCANA

The game is easy enough to learn, but before playing you'll want to watch some more detailed guides (like the one linked below), but here's the summary: 

You and opponent(s) will prepare decks with a minimum of 60 cards each. These cards can be from two ink colors max, but you could theoretically do an entire deck with one ink color. 

Each player draws seven cards from their deck to start. From there, you'll take turns, each trying to earn Lore points until someone gets to 20 total points.

To do this, you'll need to start your turn by 'inking' a card from your hand. This means you'll choose one card per turn to become a renewable ink resource, and place it face down in front of you. If you look at the top left number on your cards, this tells you how much ink you need to bring that card into play. If you've only inked one card from your hand so far, you can only bring out a card that has a one in the top left. 

As you progress through the game, you'll ink more cards, bring out more cards, and be able to quest and/or challenge.

Questing means you send your character out to get Lore points. The number you get depends on the number of Lore symbols in the bottom right corner of your card. You will automatically get however number of Lore points your card has when you quest, but, this leaves your character open to being challenged by your opponent during their turn.

Challenging means that rather than earning a Lore point, you want to attack your opponent. Compare your attack and defense stats (the sun and shield icons) and deal the appropriate damage. If you have 2 attack, and your opponent has 1 defense, they will be banished. However, if their attack is larger than your defense, you will also be banished. If their attack is smaller than your defense, your defense strength will be lowered by their attack amount for all future turns.

Many characters will have specific perks or rules attached to them, found in the lower half of the card. Pay attention to these, as they often come in very handy. You'll also have Item and Action cards in your hand. These cards will also have varying rules that come into play once they're brought out. 

Getting to 20 Lore points is easy, until Challenging comes in. Play strategically and you might walk away victorious.