Date & Time: 19.04.2020 16:30
Frequency: everytime
World name: Lich
Character name: Miliandra Shiro
Monster name: Good King Moogle Mog
Class/Level: White Mage Level 50 synced / Red Mage Lvl 80 unsynced and synced
Party or solo: both
In-game time: 19.04.2020 14:30
Area and coordinates: Thornmarch Hard

Same bug on Lich, tested on both WHM and RDM.
RDM HP at level 54 is 2.7K, can't survive the attack, and this attack is mandatory.