Two-Headed Giant (also known as 2HG) is a DCI-sanctioned multiplayer format for Magic: the Gathering in which two teams of two players each all play together in a single game.
Each team sits together on one side of the table. Each team decides the order in which its players sit. The player seated on the right within each team is the primary player, and the player seated on the left is the secondary player. Each team has a shared life total, which starts at 30 life.
Two-Headed Giant Constructed decks must contain a minimum of sixty cards. There is no maximum deck size; however, you must be able to shuffle your deck with no assistance. Teammates may review each other's hands and discuss strategies at any time. Each team takes turns rather than each player. Both the players on a team take their team turn at the exact same time.
"Beanie" cap given out at certain Two-Headed Giant events
Two-Headed Giant uses the Unified Deck Construction rules (with the exception of basic land cards, no any individual card can be used by both players in the team). Sideboards are not allowed in Constructed Multiplayer tournaments. If a card is restricted in a particular format, no more than one of that card may be used by the team. No players may use cards that are banned in a particular format.
The two players on a team act separately, just like in any other multiplayer game, with the following exceptions:
- The players share life totals and poison counters.
- When creatures attack one of its players, each player can have his or her creatures block.
- The players win or lose the game as a team. This includes concession.
In particular, the following situations treat the players individually:
- If an effect refers to "attacking player" or "defending player", it means one of them, not both and not the team. For example, when Spiteful Returned or a creature enchanted by it attacks, its controller chooses a defending player to lose 2 life.
- Damage is dealt to players, not teams, even though the resulting reduction in life total is shared. In particular, combat damage is allocated to one of the players. For example, if one player has cast Druid's Deliverance, the attacking players can simply allocate combat damage to that player's teammate.
- Life gain and loss applies individually. For example, when an opponent's Gray Merchant of Asphodel enters the battlefield, the team's life total decreases by two times X.
- Likewise, poison counters are given to individual players, although the team shares them. For example, when Ichor Rats enters the battlefield, the team gets two poison counters.
- On the other hand, effects that say a player can't gain or lose life or gain poison counters apply to the teammate as well.
In addition to the above rules, the following card is banned in Constructed Two-Headed Giant tournaments:
Up until Dominaria the rule was that creatures would attack the team, rather than one of its players. From this update on, you simply attack players or planeswalkers, not the team. This change brings Two-Headed Giant's combat in line with Archenemy, using the same shared team turns system of combat. The only difference is that the team's life total goes down rather than the individual's. It also prepared the way for Battlebond, the first-ever Two-Headed Giant focused Magic booster set.
From the Comprehensive Rules (Ravnica Allegiance (January 25, 2019))
- 810. Two-Headed Giant Variant
- 810.1. Two-Headed Giant games are played with two teams of two players each.
- 810.2. The Two-Headed Giant variant uses the shared team turns option. (See rule 805.)
- 810.3. Each team sits together on one side of the table. Each team decides the order in which its players sit.
- 810.4. Each team has a shared life total, which starts at 30 life.
- 810.5. With the exception of life total and poison counters, a team's resources (cards in hand, mana, and so on) are not shared in the Two-Headed Giant variant. Teammates may review each other's hands and discuss strategies at any time. Teammates can't manipulate each other's cards or permanents.
- 810.6. The team who plays first skips the draw step of its first turn.
- 810.7. The Two-Headed Giant variant uses the combat rules for the shared team turns option (see rule 805.10). This is a change from previous rules.
- 810.8. The Two-Headed Giant variant uses the normal rules for winning or losing the game (see rule 104), with the following additions and specifications.
- 810.8a Players win and lose the game only as a team, not as individuals. If either player on a team loses the game, the team loses the game. If either player on a team wins the game, the entire team wins the game. If an effect says that a player can't win the game, that player's team can't win the game. If an effect says that a player can't lose the game, that player's team can't lose the game.
Example: In a Two-Headed Giant game, a player controls Transcendence, which reads, in part, "You don't lose the game for having 0 or less life." If that player's team's life total is 0 or less, that team doesn't lose the game.
Example: In a Two-Headed Giant game, a player attempts to draw a card while there are no cards in that player's library. That player loses the game, so that player's entire team loses the game.
Example: In a Two-Headed Giant game, a player controls Platinum Angel, which reads, "You can't lose the game and your opponents can't win the game." Neither that player nor their teammate can lose the game while Platinum Angel is on the battlefield, and neither player on the opposing team can win the game.
- 810.8b If a player concedes, their team leaves the game immediately. That team loses the game.
- 810.8c If a team's life total is 0 or less, the team loses the game. (This is a state-based action. See rule 704.)
- 810.8d If a team has fifteen or more poison counters, that team loses the game. (This is a state-based action. See rule 704.)
- 810.9. Damage, loss of life, and gaining life happen to each player individually. The result is applied to the team's shared life total.
Example: In a Two-Headed Giant game, a player casts Flame Rift, which reads, "Flame Rift deals 4 damage to each player." Each team is dealt a total of 8 damage.
- 810.9a If a cost or effect needs to know the value of an individual player's life total, that cost or effect uses the team's life total instead.
Example: In a Two-Headed Giant game, a player on a team that has 17 life is targeted by Beacon of Immortality, which reads, in part, "Double target player's life total." That player gains 17 life, so the team winds up at 34 life.
Example: In a Two-Headed Giant game, a player controls Test of Endurance, an enchantment that reads, "At the beginning of your upkeep, if you have 50 or more life, you win the game." At the beginning of that player's upkeep, the player's team wins the game if their team's life total is 50 or more.
Example: In a Two-Headed Giant game, a player on a team that has 11 life controls Lurking Evil, an enchantment that reads, "Pay half your life, rounded up: Lurking Evil becomes a 4/4 Horror creature with flying." To activate the ability, that player must pay 6 life. The team winds up at 5 life.
- 810.9b If a cost or effect allows both members of a team to pay life simultaneously, the total amount of life they pay may not exceed their team's life total. (Players can always pay 0 life.)
- 810.9c If an effect sets a single player's life total to a specific number, the player gains or loses the necessary amount of life to end up with the new total. The team's life total is adjusted by the amount of life that player gained or lost.
Example: In a Two-Headed Giant game, a player on a team that has 25 life is targeted by an ability that reads, "Target player's life total becomes 10." That player's life total is considered to be 25, so that player loses 15 life. The team winds up at 10 life.
- 810.9d If an effect would set the life total of each player on a team to a number, that team chooses one of its members. On that team, only that player is affected.
Example: In a Two-Headed Giant game, one team has 7 life and the other team has 13 life. A player casts Repay in Kind, which reads, "Each player's life total becomes the lowest life total among all players." Each team chooses one of its members to be affected. The result is that the chosen player on the team that has 13 life loses 6 life, so that team's life total winds up at 7.
- 810.9e A player can't exchange life totals with their teammate. If an effect would cause that to occur, the exchange won't happen.
- 810.9f If an effect instructs a player to redistribute any number of players' life totals, that player may not affect more than one member of each team this way.
- 810.9g If an effect says that a player can't gain life, no player on that player's team can gain life.
- 810.9h If an effect says that a player can't lose life, no player on that player's team can lose life or pay any amount of life other than 0.
- 810.10. Effects that cause players to get poison counters happen to each player individually. The poison counters are shared by the team.
- 810.10a If an effect needs to know how many poison counters an individual player has, that effect uses the number of poison counters that player's team has. If an effect needs to know how many poison counters a player's opponents have, that effect uses the number of poison counters opposing teams have.
- 810.10b If an effect says that a player loses poison counters, that player's team loses that many poison counters.
- 810.10c If an effect says that a player can't get poison counters, no player on that player's team can get poison counters.
- 810.10d If a rule or effect needs to know what kinds of counters an individual player has, that effect uses the kinds of counters that player has and the kinds of counters that player's team has. A player is "poisoned" if that player's team has one or more poison counters.
- 810.11. The Two-Headed Giant variant can also be played with equally sized teams of more than two players. For each player a team has beyond the second, that team's starting life total is increased by 15 and the number of poison counters required for the team to lose is increased by five. (These variants are called Three-Headed Giant, Four-Headed Giant, and so on.)
From the glossary of the Comprehensive Rules (Ravnica Allegiance (January 25, 2019))
- Two-Headed Giant Variant
- A multiplayer variant played among two-player teams that each have a shared life total and take a simultaneous turn. See rule 810, "Two-Headed Giant Variant."