Guide
How the kit works
You can start a fight with Karma Wind. It consumes 20% of Blade's Max HP and deals Wind DMG equal to 40% of his Max HP to all enemies after combat starts. If he lacks enough HP for the cost, he is left at 1 HP.
Use Hellscape to consume 30% of Max HP and enter Hellscape. For 3 turns, Blade deals 40% more DMG, is much more likely to be attacked, and replaces Shard Sword with Forest of Swords. The Skill does not end his turn or regenerate Energy, so he can attack straight away.
Forest of Swords consumes 10% of Max HP, deals Wind DMG equal to 130% of Max HP to the target and 52% to adjacent enemies. It does not regenerate Skill Points. If Blade lacks enough HP for Hellscape or Forest of Swords, the cost leaves him at 1 HP.
Shuhu's Gift gives Blade a Charge when he takes damage or consumes HP, with at most one Charge per attack against him. At 5 Charges, he attacks all enemies for 130% of Max HP and restores 25% of Max HP. Cyclone of Destruction increases this Follow-Up ATK's DMG by 20% and regenerates 15 Energy.
Death Sentence sets Blade's HP to 50% of Max HP, so it raises his HP if he is below that point and lowers it if he is above it. Its damage uses Max HP and a tally of HP lost in battle, capped at 90% of Max HP. Vita Infinita changes the amount cleared from that tally to 50%; Neverending Deaths increases healing received by 20% and adds 25% of the amount healed to the tally.
Build and why
For relics, use four pieces of Longevous Disciple. Its two-piece bonus gives 12% Max HP, while the four-piece effect gives 8% CRIT Rate for 2 turns when Blade is hit or has HP consumed. It stacks twice, and Blade can trigger it through his own attacks. Eagle of Twilight Line is another option: it gives Wind DMG and advances his action after his Ultimate.
For the planar set, Bone Collection's Serene Demesne is the first choice. It gives 12% Max HP and, at 5000 Max HP, 28% CRIT DMG. Inert Salsotto is an alternative for Ultimate and Follow-Up ATK damage at 50% CRIT Rate. Rutilant Arena instead boosts Basic ATK damage at 70% CRIT Rate.
Use CRIT Rate or CRIT DMG on the body, SPD or HP Percentage on the feet, Wind DMG Boost or HP Percentage on the sphere, and HP Percentage on the rope. For substats, look for CRIT Rate and CRIT DMG first, then HP Percentage and SPD. Account for set bonuses when checking the CRIT Rate thresholds on planar sets.
The Unreachable Side is the first weapon choice: it gives CRIT Rate and Max HP, then increases DMG when Blade is attacked or consumes his own HP. That DMG effect ends after he uses an attack. Flame of Blood, Blaze My Path is next, with Max HP, Incoming Healing and an HP cost that increases the damage of the Skill or Ultimate that triggers it. A Secret Vow is a four-star option with a DMG bonus and a further bonus against enemies at an equal or higher current HP percentage.
Leveling priority
Follow the game's order: Basic ATK first, then Death Sentence, Shuhu's Gift and Hellscape. Basic ATK comes first because Forest of Swords is the attack Blade uses while Hellscape is active. The Ultimate and Talent follow because they provide separate sources of damage.
For maximum character ascension, you need 308,000 Credit, 65 Ascendant Debris and 15 each of Immortal Scionette, Immortal Aeroblossom and Immortal Lumintwig.
For all skills, you need 3,000,000 Credit, 8 Tracks of Destiny, 18 Shattered Blade, 69 Lifeless Blade, 139 Worldbreaker Blade, 12 Regret of Infinite Ochema, 41 Immortal Scionette, 56 Immortal Aeroblossom and 58 Immortal Lumintwig.
Eidolons worth it
Reborn Into an Empty Husk is worth considering for the largest change to the follow-up: it reduces the maximum Charge count from 5 to 4 and adds damage equal to 50% of Max HP to the Talent's Follow-Up ATK.
Blade Cuts the Deepest in Hell is another good stopping point. It adds damage to the designated target of the enhanced Basic ATK and Ultimate based on the Ultimate's HP-loss tally. Ten Thousand Sorrows From One Broken Dream gives 15% CRIT Rate during Hellscape, which can make building the stat easier.
Rejected by Death, Infected With Life is an option for more Max HP when Blade crosses from above 50% HP to 50% or below. If you are not aiming for E6, stopping before E3 or E5 is reasonable: those nodes raise skill levels rather than adding a new effect. You cannot reach E6 without obtaining the earlier Eidolons.
Teams
A straightforward team can use Blade with Bronya, Lynx and Silver Wolf. Bronya is a Wind buffer, Lynx is a Quantum sustain option, and Silver Wolf is a Quantum debuffer. Blade supplies Wind damage and attacks all enemies with his follow-up.
Luocha is another sustain option, while Hyacine offers Wind sustain. For a buffer slot, consider Ruan Mei or Tribbie. You can also use Pela as a debuffer or Natasha as a sustain option.
Healing is useful even though Blade can restore HP himself. His HP spending continues during his enhanced attacks, and Neverending Deaths turns part of the healing he receives into progress toward his Ultimate's HP-loss tally. Choose the other slots around the enemies you face rather than treating one element as mandatory.
Common mistakes
Do not assume Forest of Swords will refill the team's Skill Points. Plan around its lack of Skill Point regeneration, and watch Blade's HP before using Hellscape or starting with Karma Wind. Their costs can leave him at 1 HP.
Do not build only ATK when Blade's listed attacks scale with Max HP. Also check your CRIT Rate before relying on Inert Salsotto or Rutilant Arena: their damage bonuses have different thresholds. Finally, using Death Sentence at high HP lowers Blade to 50%, while using it below 50% raises his HP to that point.
