In a game of Shogun, two to four players compete to gather the most victory points by strategically building a deck of cards. Each player starts with a small deck containing a few weak cards, with which they acquire more cards with different and more powerful abilities. Some provide more of the in-game currency; others let the player perform more actions or buy more cards per turn; others let them draw more cards, harm the other players, remove unwanted cards from their decks, or do other things. As players improve their decks, they also think about how to improve their scores; a powerful deck may be worth no victory points. The game has been compared to the "draft" gameplay style of collectible card games where players vie for the best deck from a common pool of cards.
The game usually ends under one of two conditions: when the stack of Province cards (the highest-value victory card in the base game) has been exhausted, or when any three stacks in the supply have been exhausted. Players then count the number of victory points in their decks, and the player with the highest score wins. Other end-game conditions have been introduced in the game's expansions.
Since possessing victory cards is often necessary to win the game, but they usually have no value during gameplay itself, players must balance the acquisition of victory cards with useful action and treasure cards that maintain the player's ability to play effective turns. Usually, the game's main strategy is to build a deck that maximizes the player's ability to draw hands that can buy the province card (worth 6 victory points and costing 8 coins).