Akrasan Squire

In a Two-Headed Giant game, a creature “attacks alone” if it’s the only creature declared as an attacker by your entire team. If you control that attacking creature, your exalted abilities will trigger but your teammate’s exalted abilities won’t.

Some effects put creatures onto the battlefield attacking. Since those creatures were never declared as attackers, they’re ignored by exalted abilities. They won’t cause exalted abilities to trigger. If any exalted abilities have already triggered (because exactly one creature was declared as an attacker), those abilities will resolve as normal even though there may now be multiple attackers.

Exalted abilities will resolve before blockers are declared.