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Date & Time: Any time you cast Whispering Dawn/Angel Whisper and swap between seraph and eos/selene
Frequency: Any time you cast Whispering Dawn/Angel Whisper and swap between seraph and eos/selene
World name: Cactuar
Character name: Synestri Sylvaneth
Retainer name: N/A
NPC name: N/A
Monster name: N/A
Class/Level: Scholar 80
Party or solo: Solo
In-game time: Any
Area and coordinates:
Housing:
Steps:
1. Summon Eos
2. Cast Whispering Dawn
3. Summon Seraph before the duration of Whispering Dawn expires
4. Occasional regen ticks will be 1/10 the typical amount.

Likewise, you could also:
1. Summon Seraph
2. Cast Angel's Whisper shortly before Seraph's timer expires
3. Occasional regen ticks will be 1/10 the typical amount.

Mine go from 4.5 to 5K down to 400 at some ticks. I can demo in game if that helps.