In a Two-Headed Giant game, what is the threshold for losing due to poison counters?

In a Two-Headed Giant game, the threshold for losing due to poison counters is indeed 10 counters. In the context of this multiplayer format, where two players work together as a team, any player that accumulates 10 or more poison counters is eliminated from the game. This means that the team loses if one of its members reaches that count.

It is important to understand that the standard threshold for poison counters in regular games is typically 10, and this rule applies consistently across different formats, including Two-Headed Giant. The other thresholds listed in the choices do not align with the established rules for poison counters and thus do not apply in this scenario. In Two-Headed Giant, the emphasis is on cooperative play and that one player's status can determine the team's success or failure.