Boss Guide: Ch16-4 (SIN)

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Enemy Layout

Tree Has Awakened 1/1
Tree of Emptiness Mayall
Tree of Emptiness Mayall
Tree of Emptiness Mayall

Boss Statistics

Note: Master Skills are sealed for the first five turns!
Tree of Emptiness Mayall
Tree HP
Class Assassin
NP Bar
NP Type
Up to 3 per turn
Demonic, Evil, Super Giant
Normal Attack Normal attacks will hit AoE (all frontline party members). Critical attacks will hit a single target (ST).
Passive 1 Stun Nullification: Apply Stun and Pig Immune to self [Unremovable].
Passive 2 Mayall α: Increase own Quick Resist by 50% [Unremovable].
Passive 3 Mayall β: Increase own Arts Resist by 50% [Unremovable].
Break α Ring Purge: Remove [Mayall Alpha] passive. Increase own Buster Resist by 25% [Unremovable]. Decrease NP Gauge of all enemies by 20%.
Break β Ring Purge: Remove [Mayall Beta] passive. Increase own Buster Resist by 25% [Unremovable], stacks with previous buff. Decrease NP Gauge of all enemies by 20%.
Skill 1 Besieged on All Sides: Decrease NP Gauge of an enemy by 20%. Increase own NP Gauge by 1.
Skill 2 Catena: Increase own Critical Rate by 100% (2 turns).
Skill 3 Envelope: Inflict Curse on an enemy (200 damage, 5 turns). Inflict Evil Curse on an enemy (+50% Curse Damage, 5 turns).
NP Red Halation: Remove all debuffs from self. Deal damage to all enemies. Inflict Curse on all enemies (2000 damage, 5 turns).


  • Moderate Difficulty – In comparison to some of the other encounters in this Lostbelt, this is among one of the less difficult ones, being entirely possible to solo with the free Guest Support (Qin Shi Huang). It consists of a single large Assassin enemy with three break bars, capable of AoE normal attacks and an AoE NP. Its critical hits will hit a single target. As is the trend for this Lostbelt, Master Skills will start sealed, in this case for five turns.
  • Three Passives – the Tree of Emptiness is permanently Stun (and Pig) Immune, and starts with increased Quick + Arts Card Resist +50% pre-break.
  • Break 1: Drains frontline NP by 20%, Loses Quick Resist, Gains Buster Resist +25% - Upon first break, be ready for the boss to drain the entire party’s NP Gauge by 20%. Save any charging moves until after break if needed.
  • Break 2: Drains NP again by 20%, Loses Arts Resist, Gains Buster Resist again +25%, Total 50% - Upon second break, the boss will drain the party’s NP Gauge once more by a fixed 20%. This time both Quick and Arts resist will be removed, replaced by Buster Resist.
  • Can guarantee 2 turns of Critical Hits – One of the boss’s skills gives it a 100% Critical Rate for an entire two turns. This buff can be removed if the means to do so is available.
  • Able to charge own NP Gauge by 1 with a skill – The boss can randomly increase its own NP Gauge by 1 (while draining a random target’s NP by 20%) as a skill on its turn, so be wary if it is one charge away from being able to use its NP skill. Skill Seal can prevent this from being used.
  • Utilizes Curse skills – Its final skill enables it to inflict Curse on one enemy (base 200 damage, 5 turns), and also inflicts Curse Damage Up by 50% (effectively making it 300 damage with one stack). This skill’s effects can stack, and also compound with the Curse damage from the boss’s NP.
  • NP Deals AoE damage + Curse – The boss’s NP will first remove all debuffs from itself, and then deal AoE damage and inflict Curse (2000 damage, 5 turns) on the entire party. With the Curse Damage Up debuff from its skill, the damage can quickly snowball over turns, so bringing some form of sustenance or debuff clear is helpful.

Team Recommendations

  • Caster DPS is effective as always against this Assassin-class enemy, with high damage candidates being Illyasviel, Xuanzang Sanzang, or Shuten-Douji (Caster). Caster of Okeanos and Medea are also notable, both being able to cleanse debuffs (namely Curse) during this encounter, and Medea being able to remove buffs if the enemy gains its Critical Rate buff.
  • Alter Ego DPS is also an alternative, with Meltryllis being an excellent candidate if Skadi support is available, providing buff removal with her NP if required.
  • Damage and NP Gauge Support for the primary DPS is always welcome. The enemy itself will also generously fill the Servants’ NP Gauges with its normal attacks, periodically taking some away with either a skill or break effect. Merlin, Zhuge Liang, and Skadi are all excellent choices as always, bolstered by their class advantage during this fight.
  • It is also entirely possible to solo this encounter using the “Mystery” Guest Support, who is NP5 10/10/10, with a bit of support (or meat shield) Servants, reference available in the video below.

Video Links

Quick Servant Suggestions

- Recommended
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Other ST DPS
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Guest Support
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