When two expansions clash, they get layered based on affinity and type, for example, Arad's void might get filled with a red dragon's flames, allowing the two to exist at the same time. But when three powerful expansions clash, the strongest one would dominate as the mana present would hit the maximum density allowed in the air.
[Elemental Expansion: Bone Yard] As Alaric crosses his arms, a storm of bones explodes from his forearms aiming to blast both Lydia and Lunara away to give himself an opening to kill Eris. This expansion was cone-shaped instead of a spherical one, mainly because Alaric wanted to conserve energy and create an opening instead of defeating his targets or getting an advantage.
[Elemental Expansion: Moon Rain] Lunara's slashes fell from the moon as quickly as they could, aiming only at Alaric. If she could wound him enough, Arad is bound to take back control.
The durability of a demon lord can't be understimated.
Someone is about to have a really bad day.