Does a hit reduced to zero discard Rising Dark, and what if no 0-aether spell is prepped?

Question

Accepted Answer

No. Damage reduced to zero is not dealt, so the card stays in play until its power resolves. If no prepped spell costs 0 aether, nothing is destroyed but any damage is still taken.

Aeon's End: War Eternal

Does a hit reduced to zero discard Rising Dark, and what if no 0-aether spell is prepped?