What happens if a team has fifteen or more poison counters in a Two-Headed Giant game?

In a Two-Headed Giant game, if a team accumulates fifteen or more poison counters, that team loses the game. This rule is specific to the mechanic of poison counters, which signifies a player’s health being diminished not by traditional life totals but rather through the accumulation of poison.

The loss condition arises from the effect of the poison counters themselves, which are intended to provide an alternative win/lose condition in contrast to the typical life total decrease. A team in a Two-Headed Giant match consists of two players, and both players share a collective life total and board state, but poison counters specifically target each player individually, where a total exceeding fourteen poison counters results in an immediate loss condition for their team.

This distinct rule emphasizes the danger of being poisoned, creating a strategic depth around avoiding or managing the accumulation of such counters. Consequently, when a team reaches the threshold of fifteen poisoned counters, they trigger the loss condition immediately, leading to that team's defeat.