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Don QuixoteThe Index Proxy - Effloresced E.G.O:: Procuration
Follow the 
Prescript: Use her marked skill against (ideally) the marked target. Her conditionals and effects will naturally follow if you keep doing this. Activate her passive as soon as possible to speed up her 
Grace of the Prescript gain.
Failing to follow the prescript gives her 
Karmic Consequence, a stacking debuff that makes her more fragile and lasts for the rest of the encounter. She stops gaining more of it when she hits 9 Grace of the Prescript.
If possible, save her S3 for when she has 6+ Grace of the Prescript.
She gains 
Unlock stages as she follows the Prescripts. At Stage 1 and above, she enters her E.G.O state if she has 25+ SP, consuming 15 SP in the process. The first time she reaches Stage 1, if she doesn't have enough SP, she'll gain some Karmic Consequence to cover the difference and force herself into E.G.O state regardless. If she drops to 0 or less SP, she loses E.G.O state, but can gain it again if her SP goes back up.
Her E.G.O state converts her skills to stronger versions that consume SP to use, but are otherwise pretty similar.
She can force her Grace of the Prescript and Unlock level to go up by using her defense at the cost of gaining Karmic Consequence stacks. You may want to use it in unfocused encounters if you want to trigger her E.G.O state faster.
The following happens every turn:
The Prescript's Target is assigned to a random enemy, increasing damage taken from Index identities.
Mark of the Prescript is assigned to a random skill (1 per slot, 2 skills max, prioritizes S3 at 6+ Grace of the Prescript).
Gain a Prescript depending on her Grace of the Prescript. The prescript gets stricter the higher her stacks, but effectively always boils down to using her marked skill. Following the Prescript gives her SP and Grace of the Prescript, more if her target is marked.
Being in E.G.O state or 
Unlock - III gives her additional speed, offense level, defense level, 
Poise generation, and damage buffs.
Her passive increases her damage and SP healing when she follows the The Prescript's Target and Mark of the Prescript mechanics.
3 +4
62 (+2)Clash: 4-18Damage: 11.04-72.46Atk Weight:Mark of the Prescript, Final Power +1 and deal +15% damage
Coin Power +1 for every 6 (Poise on self + 
Sinking on target) (max 2)
[On Use] Gain +2 Poise Count
SinkingPoisePoise Count
4 +463 (+3)Clash: 5-19Damage: 11.04-72.46Atk Weight:Mark of the Prescript, deal +15% damage
Coin Power +1 for every 6 (Poise on self + Sinking on target) (max 2)
[On Use] Gain +2 Poise Count
[Attack End] Lose 3 SP (2 times per turn)SinkingSinking CountPoise Count
4 +463 (+3)Clash: 6-26Damage: 18-131.48Atk Weight:Mark of the Prescript, Final Power +1
Coin Power +1 for every 6 (Poise on self + Sinking on target) (max 2)
[On Use] Gain 3 PoiseSinkingSinkingPoise CountSinking Count
5 +464 (+4)Clash: 6-26Damage: 19.8-138.59Atk Weight:Mark of the Prescript, deal +10% damage
Coin Power +1 for every 6 (Poise on self + Sinking on target) (max 2)
[On Use] Gain 3 Poise
[Attack End] Lose 6 SP (2 times per turn)SinkingSinkingPoise CountSinking Count
6 +664 (+4)Clash: 11-27Damage: 62.4-202.97Atk Weight:Mark of the Prescript, Coin Power +1 and deal +40% damage on Critical Hit
Final Power +1 for every 4 (Poise on self + Sinking on target) (max 4)
[Combat Start] At 2+ Unlock stage, convert all Coins of this Skill to 
Unbreakable Coins and deal +20% damage for every Unlock stage (max 60%)
[On Use] Gain +3 Poise Count
- Gain Poise equal to current Unlock stagePoiseUnlock stage (max 120%)Sinking and +1 Sinking CountSinking and +1 Sinking Count
5 +3
65 (+5)Clash: 6-28Damage: 37.2-260.45Atk Weight:Mark of the Prescript, deal +25% damage
Coin Power +1 for every 6 (Poise on self + Sinking on target) (max 2)
[On Use] Gain +3 Poise Count
- Gain Poise equal to current Unlock stage
[Attack End] Lose 15 SP (2 times per turn)Unbreakable CoinSinkingUnbreakable CoinSinkingUnbreakable CoinSinkingUnbreakable CoinUnlock stage (max 3; max 120%)SinkingSinking Count
3 +360 (+0)Clash: 6-17Damage: 31.32-115.39Atk Weight:Unlock stage (max 3; max 45%)
[Combat Start] Gain Shield equal to 15% of max HP (once per turn)
- Reduce Shield gained by 1.5% for every 5 Karmic Consequence; at 50+ Karmic Consequence, does not gain Shield
[On Use] Gain +2 Poise Count
[Turn End] If this unit does not have Unlock, gain Unlock - I (once per turn)
- Change Grace of the Prescript Stack to 3
- Gain 5 Karmic Consequence at next Turn Start for every Grace of the Prescript gainedPoiseSinkingSinking
4 +362 (+2)Clash: 7-18Damage: 25.2-100.54Atk Weight:Unlock stage (max 3)
[On Use] Gain 3 Poise
[Turn End] At lower than stage 3 Unlock, activate the following (once per turn):
- If this unit has Unlock, increase it by 1 stage
- At less than 6/9 Grace of the Prescript, change its Stack to 6/9
- Gain 5 Karmic Consequence at next Turn Start for every Grace of the Prescript gainedSinkingSinkingPrescript: [Device] I / Prescript: [Device] II / Prescript: [Device] III / Prescript: [Device] IV based on Unlock stage on self
- Inflict The Prescript's Target to a random enemy (in Focused Encounters, the Part)
- Apply Mark of the Prescript to Base Attack Skills on this unit's Dashboard (1 per Slot, max 2 Skills)
· At 
Unlock - II+, the effect above prioritizes Skill 3
- All of the effects above and Prescript execution checks do not trigger when this unit is Staggered, Immobilized, in Panic, or in E.G.O Corrosion
If this unit has Unlock - III at Turn Start, gain  - Procuration.png)
Shin (心) - ProcurationPrescript was executed this turn, heal 4 SP and gain 1 Grace of the Prescript (once per turn)
- When executing Prescript, if the main target has The Prescript's Target, heal 8 SP and gain 3 Grace of the Prescript instead
Turn End: If Prescript was not executed this turn, gain 5 Karmic Consequence
- At Unlock - III, does not gain Karmic Consequence
- If this unit attempted to execute Prescript at Combat Start, but could not target the enemy during the combat phase, does not gain Karmic Consequence at Turn EndGrace of the Prescript, gain Unlock - I/Unlock - II/Unlock - III.
If this unit gained Unlock - I, consume 15 SP to enter Effloresced E.G.O::Procuration state:
- Before consuming SP to enter this state, heal SP to 25 and gain Karmic Consequence equal to (SP healed / 5) (rounded up)
- At Turn Start after the above checks, if this unit has Unlock and is at 25+ SP, consume 15 SP to enter this state
- If this unit gets Staggered when entering Effloresced E.G.O::Procuration state, recover from Stagger (if this unit's Stagger cannot be naturally recovered from, does not enter Effloresced E.G.O::Procuration state)
- Gain 
Faith Beyond Question while in Effloresced EGO::Procuration state
Turn Start: At 0 or less SP, this unit exits Effloresced E.G.O::Procuration state
x1
x1
x1Mark of the Prescript for every Grace of the Prescript on self (max 16%)
- At 9 Grace of the Prescript, deal +20% damage using Base Skills instead
On hit using Base Skill attacks against targets that have The Prescript's Target, heal 3 SP (once per Skill; 2 times per turn)
- Heal additional SP based on Unlock stage x3
Damage Up as well
- This effect does not apply to units under effects that prevent SP recovery such as E.G.O Corrosion, Panic, etc.