The 5th-level spell Dream at first glance seemed really flavorful, but now it looks like an absolute nightmare after a second comb through.
Is the damage from the spell tied to the save? Or does it happen regardless of the outcome?
Here's the relevant portion of the dream spell text (emphasis mine):
You can make the messenger appear monstrous and terrifying to the target. If you do, the messenger can deliver a message of no more than ten words and then the target must make a Wisdom saving throw. On a failed save, echoes of the phantasmal monstrosity spawn a nightmare that lasts the duration of the target's sleep and prevents the target from gaining any benefit from that rest. In addition, when the target wakes up, it takes 3d6 psychic damage.
You can choose to make the messenger appear monstrous (or not). If you do, then the messenger can deliver a message (or not), and then (regardless) the target is forced to make a saving throw. If the target fails the saving throw, it is subjected to a nightmare for the duration of the rest, losing the benefits of the rest. Then, in addition to that effect, the target will also take the psychic damage upon waking.
So the target only takes the damage if it fails the save. Otherwise, there was no nightmare to have ruined the rest or to have inflicted any damage.