Immortal Knight is the "second life" hidden class in Lord Nine: Infinite Class (LordNine) — an all-rounder whose signature is a death-defying safety net: drop to critical HP and the class makes you untouchable for five seconds, then refills a chunk of your health bar. Among the eight hidden classes it sits near the top of the pecking order, second only to Destroyer, and it earns that spot almost entirely in PvP.
Verified current as of the August 12, 2026 update. All skill text below matches the live in-game tooltips, cross-checked against the game data files.
How to Unlock Immortal Knight
Hidden classes in LordNine unlock automatically when you carry a specific combination of six abilities at the same time. The combo is arranged as three slots with two interchangeable options each — you need one ability from both columns of every row, active simultaneously on the same character. Order doesn't matter, and the abilities can come from any base class you've leveled.
| Slot | Option A | Option B |
|---|---|---|
| 1 |  Chase |  Defensive Stance |
| 2 |  Deathblow |  Supersense |
| 3 |  Install Bomb |  Secreta's Talent |
Swapping any qualifying ability out of your active build reverts the class until the combo lines up again — plan swaps carefully. For every other combo in the game, see the complete hidden class combination reference.
The Class Skill: a Built-In Second Life
Class Skill: When the caster's HP is at 10% or below, becomes Immortal and immune to all Damage, Status Effects, and Debuffs for 5 sec. When Immortal ends, recovers HP equal to 30% of Max HP. (Recovery cannot exceed 15,000.)
The 15,000 recovery cap sounds like a catch, but in practice it isn't one: even heavily invested endgame characters currently sit around 50,000 Max HP or below, so the 30% recovery almost never hits the ceiling. What the skill really buys you is tempo — five seconds where every point of damage and every crowd-control attempt thrown at you is wasted, followed by a heal that forces opponents to redo work they thought was finished.
The counter every Immortal Knight needs to know: if your current HP is ~20% and then you receive fatal damage that is higher than your current HP, Immortal Knight's safety net passive will not proc and you will die.
What Immortal Knight Is Actually Good At
This is a PvP-first class, full stop. The value is longevity: staying alive and uninterrupted means you keep contributing damage and pressure while opponents burn cooldowns trying to finish you. The dream scenario is baiting a kill attempt at low HP — every stun, knockdown, and burst skill spent during your immunity window is negated outright.
For pure PvE grinding there are better picks; if that's your focus, look at Sword Master for melee or Harbinger of Storms for AoE farming.
Petrification Curse at Ability Level 800
The 800 milestone adds a second panic button: self-Petrify for 5 seconds, immune to all damage and status effects — but you cannot move or act while petrified. It's an on-demand invulnerability window with a very real cost: you're a statue. That makes it situational at best — good for surviving a coordinated burst, useless for anything that requires you to keep fighting. Most players consider it the weaker half of the kit.
Build: Weapons, Stats, and Relics
Every weapon class can run Immortal Knight — the combo abilities and milestone stats are universal, so bring whatever you already play.
Relic priority: Origin of Destruction (Attack) first, then Barrier of Protection (Defense) and Magic Storm (Skill Damage) roughly equal, with Crystal of Life (HP) last. Plan the Temporal Piece budget with the relic calculator.
Ability Total Level Bonuses
| Ability Total Level | Bonus |
|---|---|
| 100 | Defense Penetration +50 |
| 200 | Movement Speed +8% |
| 300 | Attack Speed +8% |
| 400 | Attack Power +70 |
| 500 | Attack Power +75, Damage Received Decrease +3.5% |
| 600 | Landing Attack increases the caster's Accuracy and Critical Hit for 30 sec. |
| 700 | Defense Power +100 |
| 800 | Petrification Curse — Grants Petrify to the caster for 5 sec. While Petrified, the caster is immune to All Damage and Status Effects. |
Your ability total level is the sum of every ability level on your build, so any ability you level walks you up the ladder. Milestones 100–500 come fairly quickly — the game hands out Expert and Maestro scrolls often. At 600 the wall starts: promoting an ability tag from level 90 to 100 takes a Master Scroll, crafted from 10 Maestro Scrolls, and you need six of them. 700 and 800 are long-haul goals if you rely on freebies and grinding alone — the 800 milestone effectively asks for four ability tags at level 140 and two at 120, where 100→120 costs one Master Scroll and 120→140 costs two more.
Verdict
If you PvP, Immortal Knight is arguably the second-best hidden class in the game right now, behind only Destroyer — and a strong first unlock target if fights with other players are your endgame. If you never PvP, its headline mechanic will rarely matter to you.
Where Next?
- The complete hidden class combination reference — every slot for all eight classes
- Free LordNine tools — relic upgrade costs with live market prices, enhancement odds, MP sustain math, and homun probabilities
