When can the active team choose how to assign damage in a Two-Headed Giant game?

In a Two-Headed Giant game, the active team has the opportunity to choose how to assign damage at the beginning of the combat damage step. This is the moment when combat damage is actually dealt, and each team can decide how to distribute damage among opposing players or their creatures.

The combat damage step follows the declaration of attackers and blockers, but it is specifically during this phase that the players may assign damage. The rules specify that damage must be assigned in a way that takes into account the relevant combat damage interactions—either to the opposing players directly or to their creatures. This decision is crucial as it can significantly impact the game state and the outcome of the match.

The other contexts, such as during the attack phase or when blockers are declared, do not grant the active team the authority to decide how damage is assigned yet, as the rules defining combat do not allow for that decision until the damage step is reached. Thus, the correct moment for damage assignment aligns specifically with the onset of the combat damage step, making it the appropriate choice for understanding how combat functions in Two-Headed Giant games.