The Spymaster gives one-word clues that can point to multiple words on the board. The other players on the team attempt to guess their team's words while avoiding the words of the other team.
Twenty-five Codename cards, each bearing a word, are laid out in a 5×5 rectangular grid, in random order. A number of these words represent red agents, a number represent blue agents, one represents an assassin, and the others represent innocent bystanders.
The teams' spymasters are given a randomly-dealt map card showing a 5×5 grid of 25 squares of various colors, each corresponding to one of the code name cards on the table. Teams take turns. On each turn, the appropriate spymaster gives a verbal hint about the words on the respective cards. Each hint may only consist of one single word and a number. The spymaster gives a hint that is related to as many of the words on their own agents' cards as possible, but not to any others as this could accidentally lead their team to choose a card representing an innocent bystander, an opposing agent, or the assassin.
The hint's word can be chosen freely, as long as it is not any of the words on the code name cards still showing at that time. Code name cards are covered as guesses are made.
The hint's number tells the field operatives how many words in the grid are related to the word of the clue. It also determines the maximum number of guesses the field operatives may make on that turn, which is the hint's number plus one. Field operatives must make at least one guess per turn, risking a wrong guess and its consequences. They may also end their turn voluntarily at any point thereafter.
After a spymaster gives the hint with its word and number, their field operatives make guesses about which code name cards bear words related to the hint and point them out, one at a time. When a code name card is pointed out, the spymaster covers that card with an appropriate identity card – a blue agent card, a red agent card, an innocent bystander card, or the assassin card – as indicated on the spymasters' map of the grid. If the assassin is pointed out, the game ends immediately, with the team who identified him losing. If an agent of the other team is pointed out, the turn ends immediately, and that other team is also one agent closer to winning. If an innocent bystander is pointed out, the turn simply ends.
The game ends when all of one team's agents are identified or when one team has identified the assassin. The winner is the team who identifies all their agents first.
There have been alternate versions of the main game released over the years:
This version keeps the basic elements of Codenames — give one-word clues to try to get someone to identify your agents among those on the table — but now you're working together as a team to find all of your agents.
Codenames really is genius in it's simplicity. It's a fantastic party game because it can be taught in under 5 minutes and provides a ton of fun. Perfect for you next game night with family and friends.
You can get your copies here: Codenames