#Building a deck
A deck is exactly 15 cards, built from cards you own. You start with a playable starter deck, so you can ignore this page until you've won a few matches and have cards worth swapping in.
#The rules
| Rule | Value |
|---|---|
| Deck size | Exactly 15 cards |
| Copies of a common | Up to 2 |
| Copies of a legendary or mythic | 1 |
| Opening hand | 5 cards, with one mulligan before turn 1 |
| Draw | 1 card at the start of each of your turns |
Fifteen cards and a five-card opening hand means you see a third of your deck immediately, and most of it over a full match. There is very little room to "include one for the situation": a card you draw once every three matches is effectively not in your deck.
#What every deck needs
Rank-1 cards, more than you think. You can only play a card on a tile at its rank or higher, and you begin with three rank-1 tiles and nothing else. A deck top-heavy with rank 2 and 3 will sit in your hand on turn one, which hands your opponent the board while you're still setting up. Every CPU deck in the game carries at least seven rank-1 cards, including the hardest one.
Cards that spread wide. Pawn patterns are how you reach the middle of the board. A card whose pattern only covers the tile in front of it wins you nothing positionally, however much power it has.
A way to remove something. Placed cards are immune to pawn spread, so without abilities that damage, a well-placed enemy card is permanent. One or two removal options turn a lost lane into a contested one.
#Building around lanes
Power is not the deciding number: lanes are. A deck of enormous cards that all want the same lane will win that lane by a mile and lose the other two.
Aim to be able to contest all three lanes cheaply and win two of them properly. In practice that means a spread of ranks, patterns that push sideways as well as forward, and enough cheap cards that you always have a legal play.
#Practical advice
- Change one thing at a time. Fifteen cards is small enough that swapping four at once tells you nothing about which swap helped.
- Mulligan aggressively. A hand with no rank-1 card is usually worse than a random new one.
- Look at what beat you. The CPU decks are fixed lists, so if a Grandmaster deck keeps taking your left lane, that's a repeatable problem you can build against.
Your decks are saved to your arcade account, so they follow you to any machine. Building a deck of your own also earns the Deck Builder achievement.
Next: cards and rewards.