Waveskimmer Aven

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.

If you declare exactly one creature as an attacker, each exalted ability on each permanent you control (including, perhaps, the attacking creature itself) will trigger. The bonuses are given to the attacking creature, not to the permanent with exalted. Ultimately, the attacking creature will wind up with +1/+1 for each of your exalted abilities.

Exalted abilities will resolve before blockers are declared.