Passive - Shadow Poison
Priority: ⭐️⭐️⭐️⭐️
Summary: When the boss performs a single-target attack, there is a chance it will increase the damage dealt by Wisps and command them to assist. This chance decreases as the number of debuffs on the Wisps increases. When a Wisp is defeated, it deals damage to the boss.
Countermeasures: You'll need a tank with high survivability, such as Horrus, Eurion, or Ergander. It's also recommended to use AOE damage dealers from schools like Frost or Poison who can inflict debuffs on multiple targets to help clear the Wisps.Poisonous Fletching
Priority: ⭐️⭐️⭐️
Summary: Deals AOE damage, dispels 1 buff, and summons up to 2 new Wisps.
Countermeasures: Time your buffs carefully and use your AOE damage dealers' ultimate skills after the boss casts this skill to quickly defeat the Wisps.Harpy's Wrath
Priority: ⭐️⭐️
Summary: Deals global damage and grants a shield to all allies.
Countermeasures: Consider using heroes with the ability to dispel shields, such as Shook, Brody, or Khrysos, to defeat enemies more efficiently.Harpy's Breath
Priority: ⭐️⭐️⭐️⭐️
Summary: Unleashes a series of high-damage attacks on a single target.
Countermeasures: Mitigate the boss's burst damage with effects like Attack Penalty and Damage Reduction. Keep your tank alive with timely shields and healing.
 The main difficulty in the Grave of Venom is the enemy's powerful single-target damage, making a tank with excellent survivability an absolute necessity.
For supports, you'll need heroes who can provide constant healing or shields to keep your tank alive, as well as those who can inflict Attack Penalty or Damage Reduction to mitigate the burst damage from the boss's Harpy's Breath skill.
On difficulty 9 and above, having a support hero who can dispel shields will significantly speed up your runs.
Using damage dealers from schools like Frost or Poison to clear the Wisps can also reduce the pressure on your tank.
 Summary: No matter what, you'll need a tank like Horrus who can withstand the combined assault of the boss and the Wisps. Estella, who can increase allies' shields and healing received while providing healing over time, is also essential for survival. Make sure the boss is inflicted with Attack Penalty before it casts Harpy's Breath — Shook is perfect for this, and he can also dispel the AOE shields from Harpy's Wrath.
 Summary: Activating a 5-hero affinity bonus will significantly ease your challenge. Thanks to his passive invincibility, Eurion can easily hold out until allies provide him with shields and healing. By alternating his ultimate skill with Felosia's, Eurion can maintain a constant state of Damage Reduction. As for the pathetic shields generated by Harpy's Wrath, the powerful burst damage from Lossenia and Hvitar will shatter them in an instant.