Title explains the whole situation but I'll say it again more verbosely:
The amp provided by Radiant Daggers (Celeste's 3) applies to all spirit damage dealt by Celeste except sources of spirit damage that don't scale with spirit power. Examples include Scourge, Capacitor (the active, not the passive), Lightning Scroll, and presumably the flat explosion portion of Spirit Burn's damage.
This doesn't seem intended; surely her spirit amp should apply to all spirit damage.
The amp provided by Radiant Daggers (Celeste's 3) applies to all spirit damage dealt by Celeste except sources of spirit damage that don't scale with spirit power. Examples include Scourge, Capacitor (the active, not the passive), Lightning Scroll, and presumably the flat explosion portion of Spirit Burn's damage.
This doesn't seem intended; surely her spirit amp should apply to all spirit damage.