The term "Herald of Death" carries multiple meanings in the broader Honkai universe, but in the context of Honkai Star Rail's Version 4.0 update — titled "No Aha at Full Moon" — it refers to a specific and deeply unsettling figure within the world of Planarcadia. The Herald of Death is a mass murderer who disrupted the Phantasmoon Games 15 years ago, and they have now returned during the current iteration of the games with lethal intent.
Quick answer: The Herald of Death is an unidentified killer in Planarcadia who sabotaged the previous Phantasmoon Games and has resurfaced during the current ones, having already wiped out the entire Synwish Syndicate. Himeko appears to have a personal connection to this figure, though the full nature of that link remains unresolved in the 4.0 storyline.
What Are the Phantasmoon Games?
To understand the Herald of Death's significance, you need to understand the event they're disrupting. The Phantasmoon Games occur roughly every 15 years in Planarcadia, triggered when the world's special moon — manifested through the power of Elation — becomes full. During the games, eight masked participants called Supplicants compete for an audience with Aha, the Aeon of Elation. The winner receives Aha's authority for a brief window, allowing them to wish for essentially anything.
Participation requires finding and wearing a unique Phantasmoon game mask. Each Supplicant must publicly declare themselves, create a miracle to attract attention, and ultimately generate the most "wishpower" through elation to win. The stakes are enormous, and the Herald of Death's interference makes them even more dangerous.
The Herald of Death's History in Planarcadia
Fifteen years before the current storyline, the Herald of Death threw the previous Phantasmoon Games into chaos. The specifics of what happened during that earlier disruption haven't been fully detailed in the 4.0 Trailblaze missions, but the aftermath was severe enough that the Herald became a figure of fear across Planarcadia. Their return during the current games is treated as a genuine crisis by the characters involved.
The Herald's most notable act in the present timeline is the murder of the entire Synwish Syndicate. This isn't a subtle threat or background lore detail — it's a central plot point that drives much of the tension in the Version 4.0 story. The killer's true identity remains unknown, and they are speculated to be one of the eight Supplicants, potentially wearing the Octopus mask.
Himeko's Connection to the Herald
One of the most intriguing threads in the 4.0 storyline is Himeko's apparent connection to the Herald of Death. Planarcadia is described as Himeko's home world, and the narrative positions her closer to the central conflict than she has been in any previous arc. For a character who has spent much of Honkai Star Rail's runtime confined to the Astral Express — often sidelined while younger crew members take the lead on planetary missions — this is a significant shift.
The community has long debated Himeko's narrative role, largely because her counterpart in Honkai Impact 3rd famously died. Many players have worried that HoYoverse might repeat that fate. The 4.0 storyline leans into this tension by placing Himeko in proximity to a figure literally called the Herald of Death. Whether this is a deliberate misdirect or genuine foreshadowing remains to be seen, but the writing clearly wants players to feel uneasy about her safety.
That said, HoYoverse has a well-established pattern of avoiding permanent deaths for playable characters in Honkai Star Rail. Characters like Firefly and Tingyun have been "killed" only to return in subsequent patches. The only characters who have genuinely ceased to exist — Misha and Gallagher — were Memoria-based life forms in Penacony's Dreamscape, meaning they were never traditionally alive to begin with.
The Phantasmoon Games Supplicants and the Octopus Mask
Eight masks correspond to eight Supplicants in the Phantasmoon Games. Five have been confirmed so far in the 4.0 storyline:
| Mask | Supplicant |
|---|---|
| Raccoon | Trailblazer |
| Bunny | Sparxie and Sparkle |
| Raven | Sunday |
| Wolf | Ashveil |
| Cat | Silver Wolf |
Three masks remain unconfirmed: the Fish Fins, the Fox, and the Octopus. The Fox mask is speculated to belong to Himeko, while the Octopus mask is the prime candidate for the Herald of Death. The Fish Fins mask may belong to Pearl. None of these have been officially confirmed within the 4.0 missions, so treat them as educated guesses for now.
Not to Be Confused With Castorice's "Wail, Death's Herald"
If you've searched for "Herald of Death" and stumbled across Castorice's Technique ability called "Wail, Death's Herald," that's an entirely separate thing. Castorice is a 5-star Quantum Remembrance character from Amphoreus who was released in Version 3.2. Her Technique puts her into a "Netherveil" state for 20 seconds, preventing enemies from approaching and summoning her memosprite Netherwing when she initiates combat. The name is thematically fitting for Castorice — who carries titles like "Servant of Death" and "Daughter of the River of Souls" — but has no narrative connection to Planarcadia's Herald of Death.
Why the Herald of Death Matters for the 4.0 Arc
The Herald of Death serves as the primary antagonistic force in the Planarcadia storyline, injecting real danger into what could otherwise be a lighthearted competition arc. The Phantasmoon Games are fundamentally about joy and elation — they exist under the domain of Aha, after all — so having a serial killer lurking among the Supplicants creates a sharp tonal contrast that drives the narrative forward.
The mystery of the Herald's identity also gives the 4.0 arc a detective-story quality that distinguishes it from previous world arcs like Amphoreus or Penacony. Players are meant to piece together clues alongside the Trailblazer, and the Herald's connection to Himeko adds personal stakes for the Astral Express crew in a way that the game has been building toward for a long time.
With the 4.0 story still unfolding, the Herald of Death's full identity and motivations will likely be revealed in subsequent patches. For now, they remain one of the most compelling mysteries Honkai Star Rail has introduced — and a welcome excuse to finally give Himeko something meaningful to do.
