Rule 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.