// In that case, the other player does so when the spell or ability’s controller normally would do so.
// If there is more than one other player who could make such a choice, the spell or ability’s controller decides which of those players will make the choice.
UUID playerId = null;
if (modeChooser == TargetController.OPPONENT) {
TargetOpponent targetOpponent = new TargetOpponent();
if (targetOpponent.choose(Outcome.Benefit, source.getControllerId(), source.getSourceId(), game)) {
playerId = targetOpponent.getFirstTarget();
}
} else {
playerId = source.getControllerId();
}