Historical Rules · 13 July 2018
Rule 810.9
Official source text from the 13 July 2018 Rules release
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.