Rinoa

One of four Doppels, Rinoa represents [ Water ].

Rinoa, Haine, and Kyrie are the other 3 Doppels.

Biograph
One of the superbosses in the Labyrinth of Chaos, Rinoa is summoned alongside 3 others.

Upon defeating her, Rinoa talks to the party, and they all vanish.

Attacks

 * Basic Attack - One Foe
 * Demon Slayer Dance - Random 4 Foes, Physical, 3 Turn Cooldown
 * Cloudy Shockwave Blade - All Foes, Physical, 3 Turn Cooldown
 * Serene Demon Sword - All Foes, Water Attribute, 3 Turn Cooldown
 * Grand Cross - All Foes, Auto Hit, Holy Attribute, Ascension 10%, 3 Turn Cooldown, 10 MP
 * Heaven's Worm - One Foe, Pleasure Attribute, Bind 50%, Slimed 75%, 3 Turn Cooldown
 * Meditation - Self, Heal 40% of Max Health, 10 Turn Cooldown, 5 MP
 * All Slow - All Foes, Magical, Slow 75%, 3 Turn Cooldown, 8 MP
 * All Quick - All Allies, Quick for 5 turns, 3 Turn Cooldown, 8 MP
 * Undine - All Foes/Self Buff, Magical, Water Attribute, Gain "Undine" + 50% Will/Crit Chance/Dex/Accuracy/Magic Evade + Water Absorb + Water Strike + Water Booster 50% for 3 Turns, 3 Turn Cooldown

Strategy
These Doppels are weak for a super boss if they fought alone, with their easily accessible weak points and more than one way to debuff them. Its because they fight together, that they become the second hardest super boss of Paradox part 2.

Rinoa is a mix between a support and an attacker. She doesnt have the most health of the party (Shes only has a base difference of 40 K from Holly, who has the least health), but with Meditation, she can heal a huge chunk of her life back every 10 turns. Alongside that, she can slow the entire party, while speeding her side up, making it unlikely that physical attacks will hit them. On the offensive side, Rinoa has rather basic attacks, but due to the massive difference in stats, they should deal a one hit kill to the any one they touch, even more so after being buffed by her teammates.

The entire team of Doppels can be insta killed if they are inflicted with Slimed, using Alma Elma's (Queen Succubus) Orgasmic Ascension. Another easy way to beat the party is to drain all four of the Doppels and just use Waning Moon Dance afterwards, as they do not have non physical attacks after being drained of mana.

Check here and here for detailed information on all the superbosses and everything you can make use of to defeat them.