Consumes HP equal to 20% of Mortenax Blade's maximum HP and inflicts Fire damage equal to 36% of Mortenax Blade's maximum HP to all enemies, and additionally inflicts 8 instance(s) of damage, with each instance dealing Fire damage equal to 12% of Mortenax Blade's maximum HP to one random enemy. If the current HP is insufficient, Mortenax Blade's current HP will be reduced to 1 when he uses Skill. While not in the "Infinite Fury" state or when the current HP is 1 or lower, Mortenax Blade cannot use his Skill. Using Skill does not consume Skill Points.

Mortenax Blade moves, skills and special abilities
Mortenax Blade: 5-Star, Fire, Nihility. Faction: Stellaron Hunter — ???.
Skills
1Ultimates
2Inflicts "Balefire Bind" on all enemies. Enemy targets in the "Balefire Bind" state have their DEF reduced by 20% and the damage they receive increases by 30% , lasting for 4 turn(s). Then, consumes HP equal to 40% of Mortenax Blade's maximum HP to deploy a Zone. While the Zone is active, Mortenax Blade enters the "Infinite Fury" state. During the "Infinite Fury" state, increases CRIT Rate by 40%, increases CRIT damage by 30% , enhances Basic ATK, unlocks Skill, and gains a new Ultimate "Tenax Per Ignem." When receiving a killing blow, this unit will not be knocked down, but will dispel the Zone, exit the "Infinite Fury" state, and restore HP equal to 100% of this unit's maximum HP.
Source details & verification
Mortenax Blade can accumulate up to 160 overflow Energy. After using Ultimate, clears it and regenerates a corresponding amount of Energy. When the battle starts or when the Zone is dispelled, if Energy is below 150%, it is immediately regenerated to 150%. When Energy is regenerated to its maximum, dispels all debuffs from this unit.
Source details & verification
Talent
1While the Zone is active, after each attack an ally target uses on an enemy, inflicts the "Balefire Bind" state on the corresponding enemy target and grants 1 Charge to Mortenax Blade. When Charge reaches 18 points and the current HP is more than 1, consumes 18 Charge, regenerates 15 Energy, and enables Mortenax Blade to use Skill 1 extra time. This extra Skill use is considered as Follow-Up ATK.
Source details & verification
Bonus Trace
3While the Zone is active, ally targets deal 100% increased damage. If there are other Nihility characters aside from Mortenax Blade in the team, Ultimate damage dealt by ally targets increases by 150%. Otherwise, damage dealt by Mortenax Blade additionally increases by 150%.
Source details & verification
While the Zone is active, increases the chance of being attacked by enemies, decreases damage taken by this unit by 100%, and increases Incoming Healing by 100%. After being attacked, inflicts the "Balefire Bind" state on the corresponding target, and enables Mortenax Blade to gain 1 Charge.
Source details & verification
Immediately attacks all enemies within a certain range. After entering combat, inflicts the Taunt state on all enemies for 1 turn and decreases damage taken by this unit by 180% for 4 turn(s).
Source details & verification
Stat Trace
9CRIT Rate increases by 5.3%
Source details & verification
maximum HP increases by 6%
Source details & verification
Fire damage increases by 4.8%
Source details & verification
CRIT Rate increases by 4%
Source details & verification
Fire damage increases by 4.8%
Source details & verification
Fire damage increases by 6.4%
Source details & verification
CRIT Rate increases by 2.7%
Source details & verification
Fire damage increases by 3.2%
Source details & verification
maximum HP increases by 4%
Source details & verification
Basic Atk
1Inflicts Fire damage equal to 25% of Mortenax Blade's maximum HP to one designated enemy, and causes the target to enter the Taunt state for 1 turn. A Tempered Blade Severs Souls Inflicts Fire damage equal to 50 % of Mortenax Blade's maximum HP to one designated enemy, and causes the target to enter the Taunt state for 1 turn.
Source details & verification
Eidolon
6While the Zone is active, decreases all enemies' All-Type RES by 40%. After using the extra Skill from Talent, the "Infinite Fury" countdown has its action delayed by 30%.
Requirements / unlock: Eidolon 1
Source details & verification
When an ally character uses Ultimate to deal damage, it is considered as having launched Follow-Up ATK. And the Follow-Up ATK damage dealt by ally targets increases by 150%. The upper limit of Mortenax Blade's Charge decreases to 14.
Requirements / unlock: Eidolon 2
Source details & verification
Ultimate Lv. +2, up to a maximum of Lv. 15. Talent Lv. +2, up to a maximum of Lv. 15.
Requirements / unlock: Eidolon 3
Source details & verification
"Heart, Refined ad Infinitum" additionally increases ally targets' damage dealt by 100%.
Requirements / unlock: Eidolon 4
Source details & verification
Skill Lv. +2, up to a maximum of Lv. 15. Basic ATK Lv. +1, up to a maximum of Lv. 10.
Requirements / unlock: Eidolon 5
Source details & verification
As the Zone persists, when Mortenax Blade takes damage or consumes HP, he gains 1 Charge. This effect can trigger again after any target's turn ends. The damage multiplier of "Tenax Per Ignem" increases to 300% of its original value.
Requirements / unlock: Eidolon 6