Exactly the same mechanics as normal mode but with a thicker hp bar, phase 2 doesn't seem to be working as intended but you can try using the same strategy if damien decides to stay at the left all the time. Could have cleared with 0 deaths if not for the stupid mistakes in phase 2.
A fair way to estimate whether you are potentially able to solo hard lotus can be by clearing mulung dojo floor 53(54 to be extra safe) as well as having around 96% or above ied(with Priere D'Aria for phantoms). Definitely could have cleared it with even lower damage with perfect executions in the burst and mini burst cycle.

Points to take note:
(for jobs without stance)get mihile link skill! the flying sword can be extremely frustrating without stance
set background and effects to the lowest if you have latency issues, high latency can cause the sword to be bugged and spawn multiple swords that will not despawn.
(for thief classes with darksight)you can use darksight to avoid taking damage from his fireball
(for phantoms)not using final feint at the start is recommended as it will be needed during freud charges to prevent loss of buff through taking fatal damage.(cancel the final feint after freud is max)
(for 3mins burst jobs) use blood for blood(ready to die) along with angelic buster link skill in between burst cooldown to optimise damage output
Tips and tricks on the boss mechanics will be the same as normal damien as there really is no difference the two difficulties other than the insane hp hard mode has compared to normal.

Phase 1:
move to the corner of the map when the sword is targeting you(you can tell if there is appearing crosshair on your character) and about to land on the ground
highly recommended to cleanse your brand when it reaches at least 4 stacks , make sure the sword lands on the ground somewhere else before cleansing it, otherwise the sword can be a nuisance
(for phantom)use Rosa Carte Finale when damien is in his diving animation
when damien is in his dashing animation, if you are behind him after he dashes, do not jump over to him straight away, there is a 35 seconds delay with his knockback except when you are infront of him, but be sure to know the range of his dash to attempt to be in front of him.
the same goes for his diving skill as well, there is also a delay of knockback if u jump over to him except when you are already standing beside the spot he is going to land provided you are familiar with the range of the skill


Phase 2:
use all your burst at the start as more blue orbs spawn as damien's hp gets lower
blackjack will be your main source of damage in phase 2, avoid being inside the blue orb while casting blackjack
damien's diving skill is now a 1hit ko skill, avoid being beside it and instead stay underneath him and use Rosa Carte Finale
damien's dash skill is now instantly cast, however you can duck down to dodge it
damien now has a new skill(fire tornado) that he cast occasioanlly and shoots two lines of fireball in both direction, if he cast it at either corners of the map, rush to the other side of the map, if he cast near the middle which prevents both sides to be safe, do not panic and jump pass every fireball

Thats all the tips i can provide based on my experience, good luck to anyone trying to clear this boss and keep practicing!

Songs used:
Tobu Seven [NCS Release]
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Diviners feat. Contacreast Tropic Love [NCS Release]
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Jim Yosef Imagine [NCS Release]
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Diviners Savannah (feat. Philly K) [NCS Release]
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