You’re finally there. Your raid has survived the treacherous, slippery climb up the icy stairs of the Vault of the Incarnates. You’ve dodged the tornadoes, you’ve managed the sticky webs, and the boss is almost dead. Then, it happens. Your spells start hitting for nothing. The health bar isn't moving. Your combat log is a sea of "Immune" or negligible numbers.
Sennarth stopped taking damage, and honestly, it’s one of the most frustrating things that can happen in World of Warcraft right now.
It isn't just a "bad pull." It’s often a literal mechanical brick. While modern WoW is usually pretty polished, this specific encounter with the "Cold Breath" has developed some nasty habits in late 2025 and 2026, especially for players going back for transmog or achievement runs. Whether she’s evading, stuck in a 99% damage reduction loop, or simply despawning, the result is the same: no loot.
The 99% Shield That Won't Go Away
Most players who think Sennarth is bugged are actually running into a mechanic that feels like a bug but is technically part of the script. It’s the Apex of Ice.
When Sennarth reaches the final top platform, she enters a transition phase. She cocoons herself in a shield that reduces all incoming damage by 99%. During this time, she’s channeling a massive, ramping AoE that will eventually wipe the raid if you just stand there.
The fix is simple, yet people miss it constantly in the chaos: you have to interrupt her.
Once that cast is kicked, the 99% damage reduction falls off, and Phase 2 officially begins. However, here is where it gets weird. If your group interrupts her too fast—like, the micro-second she starts the cast—the game's script sometimes fails to register the transition. You end up with a boss that is "interrupted" but keeps the damage reduction buff permanently.
It's a classic case of the game's code moving slower than a modern DPS burst.
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The Infamous "Evade" Bug at the Top
This is the "true" bug. It’s been plagueing solo players and small groups throughout 2025. You get to the top, Sennarth is there, you throw a Moonfire or a Heroic Throw, and she just... resets. Or worse, she stays there, greyed out, and "Sennarth stopped taking damage" because she is stuck in an Evade loop.
This usually happens because of a desync between the boss and the adds.
In the current version of the game, Sennarth is programmed to wait for certain trash mobs to be cleared or for the raid to be within a specific "trigger zone" on the stairs. If you’re a high-mobility class like a Demon Hunter or Evoker and you zip to the top way ahead of the "intended" pathing, the boss thinks nobody is actually fighting her.
She's at the top. You're at the top. But the game thinks you’re still at the bottom.
How to Force a Fix
If you’re stuck in this Evade loop, try these steps. They're annoying, but they work:
- The Death Reset: Everyone in the raid needs to die or feign death/invisibility. If one person is still alive at the bottom of the stairs, the boss won't reset properly.
- The "Wonky" Solution: Have one person stay at the very top (at least 40 yards away from the spawn) while another person triggers the fight at the bottom. Do not kill the initial trash too quickly.
- Relogging: It sounds like "IT 101" advice, but relogging while standing on the top platform has been reported by players on the Blizzard forums as a way to "force" the boss into a killable state.
Why Speed is Actually Your Enemy
In 2026, we are doing so much damage that we’re breaking the internal timers of older raids.
Sennarth is a scripted "climb." If you push her health too low while she is still on the first or second platform, the game tries to skip her movement animations. This is a recipe for disaster. If she "warps" to the top because her health hit a certain threshold before her timer did, she often arrives in a "non-combat" state.
She'll just sit there. You can't target her, or if you can, she won't take damage.
Pro tip: If you're doing this for transmog, stop attacking her at around 40% health during the climb. Let her do her little walks. Let the dialogue play out. Once she is firmly planted on the final platform and casts Apex of Ice, then you can melt her into a puddle.
Dealing with the "Slipped Through the Floor" Glitch
Sometimes Sennarth doesn't just stop taking damage; she stops existing.
There is a known issue where she falls through the geometry of the icy stairs. When this happens, she is technically 100 yards below the map. Your AOE might still show "Immune" because you're technically "in range" of her vertical axis, but your direct attacks can't find a path.
If you see her start to jitter or sink into the ramp, stop everything.
Back away. If she resets naturally, she’ll respawn at the start. If you keep pushing, you might lock the instance, requiring a full 30-minute soft reset (everyone out of the instance) to fix it.
Actionable Steps to Guarantee a Kill
Don't let a buggy spider ruin your week. If you want to avoid the "stopped taking damage" headache, follow this checklist:
- Don't skip the stairs: Even if you can fly or leap, walk up the path. The triggers are tied to the terrain.
- Watch the cast bar: Wait for "Apex of Ice" to actually show a progress bar before you interrupt it. Kicking it at 0.1 seconds is a bug risk.
- Manage the adds: If you're soloing, make sure the small spiders aren't stuck at the bottom. Sometimes the boss stays immune until the "wave" is technically over.
- Check your debuffs: If you have too many stacks of "Pervasive Cold," you might just be dying so fast it feels like she's immune because you can't get a cast off.
Basically, just slow down. Sennarth is a diva; she needs her stage time. Give her the 3 minutes she wants to climb that hill, and she’ll give you the loot you're after.
If the boss is currently greyed out and you're reading this while standing on the platform: everyone leave the raid, wait 30 minutes, and try again without using movement-speed exploits on the stairs. It’s the only way to be sure.