for some reason I thought I already posted this thread... sorry to keep everyone waiting.
Sphinx -
Well, like all others, we have the beginner, standard, expert, etc...
Sphinx hits fairly hard in normal raging turns, can randomly do up to 3-4K to 2 Kami, so make sure you have ATK debuffs at the ready... if you're not using dark team, the second best suggested would probably be water (for the healers, curing debuffs and plenty of ATK debuffs)
Ultimate/Ragnarok Battle - 1M HP, 2 turn charge meter, she's kind of similar to Yata-Dullahan combined. Normal overdrive deals damage to allies, with the debuff that lasts for 2T (HP does not recover), while Raging overdrive deals large damage to all allies and cursing them with the instant death debuff, ("Immediate death after 2 turns") unless cured.
Strategy for non dark-main:
The best way to achieve a victory is to not lower the defense in the beginning, but lower ATK only. This way you'll be able to keep her from being raging for longer, so you're able to deal damage and get your burst gauge up fast. Let her use her normal overdrive on you, and (if) you're using Mordred/anyone with BP, Satan, etc, you can also keep her from getting her raging overdrive when she eventually becomes raging just by delay. You should try to get her stunned as quick as possible, using your burst only when raging if you can.
The estimated overall ATK for both Ultimate and Rag are 24K and 30K, so actually lower than a lot of others.
Recommended Team:
Blocking debuff kami: Hades, SR Amon, etc
Debuff cure: Sol, Aphrodite, Belobog, Atum..
Delaying overdrive: Satan, Cthulhu, Raphael, etc
Debuffs: SSR Amon (-25% DEF A-frame), Balor (dizzy, blind...) Nyarlathotep (15% def debuff gAy frame) Thanatos, Hades ...
Healers: Osiris..
Recommended Soul:
Vivian (can be a dark healer rather than using another element, also curing debuffs)
Mordred (low atk/def debuffs, but BP is needed if no kami with that or no Satan)
Arc (Regen postpones immediate death debuff, 40% cut damage with raging overdrive)
Vritra -
Normal ATK - around 2K to 1 ally
Normal Overdrive - 3-4K to all allies
Raging ATK - again, around 2K to 1 ally
Raging Overdrive - 4-5K to 3 random allies
(just from what I've seen from videos, though i'm not 100% sure.. correct me if I'm wrong. and that's without ATK debuff, so it can be lowered... a lot, also luckily she has no debuff to allies or buff to herself. just hit hard, can be tricky without healer.. also maybe also good idea to use Mordred for max overdrive so not as many strong attacks..?)
Smol edit
Recommended Team:
a n y b o d y and kirin
(literally just copied and pasted from original threads)
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Rewards:
Event Missions:
New Kamihime:
SSR Light Healer - Atum
SR Light Balance - Djehuty/Thoth
R Light Offense - Aten
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Good luck!