The accordionist of the Grimm Troupe who turns on his Master, gives the third Flame, and leads the Knight to the Nightmare Lantern for the Banishment ending.
Brumm is the only Hollow Knight NPC who actively asks the Knight to break the questline he is part of. According to the wiki, he is a member of the Grimm Troupe, plays the accordion inside Grimm's tent in Dirtmouth, and eventually leads the Knight to the Nightmare Lantern in the Howling Cliffs to destroy it.
Per the wiki, Brumm "does not approve of the Ritual playing itself out repeatedly and endlessly, considering himself and the rest of the Troupe slaves to it." His Dream Nail dialogue puts the same idea in one sentence: "Master... are even you a slave? If so, let our chains be broken together!"
The wiki specifies that Brumm appears in three locations across the Grimm Troupe quest: in Dirtmouth's tent during the Flame collection, in the Distant Village after Grimm is defeated (where he gives a Flame if the Knight has fewer than three), and in the Howling Cliffs at the Nightmare Lantern, where he jabs his staff into the brazier so it can be broken.
This guide covers Brumm's accordion role inside the Troupe, his three appearance points, the third-Flame pickup in the Distant Village, the Nightmare Lantern banishment sequence in the Howling Cliffs, the "Master... are even you a slave?" Dream Nail line, and the amnesic bug Nymm who appears in Dirtmouth if the Knight chooses Banishment over the Ritual.
Brumm, the Grimm Troupe accordionist who turns on the Master.
Inside Grimm's tent first, then Distant Village, then the Howling Cliffs Nightmare Lantern room.
A Flame in Distant Village if the Knight has fewer than three.
Joins the Knight at the Lantern and jabs his staff into the brazier so it can be broken.Brumm is the conscientious objector inside the Grimm Troupe. Per the wiki, "Brumm is a member of the Grimm Troupe. Although he initially encourages the Knight to search for flames for the Grimmchild, he begins having second thoughts about the Ritual later on."
According to the wiki, his objection is structural, not moral. The wiki specifies that "he does not approve of the Ritual playing itself out repeatedly and endlessly, considering himself and the rest of the Troupe slaves to it." His position is that the Troupe and Grimm himself are all captive to the cycle, and breaking the cycle frees the captives.
The wiki notes the more local complaint: "Brumm believes the gathering of flames desecrates the dead Kingdom of Hallownest. He wants to make the Ritual fail by destroying the Nightmare Lantern, the anchor keeping the Grimm Troupe in Hallownest." The Lantern in the Howling Cliffs is the in-fiction tether; smashing it sends the Troupe away.
Brumm first appears as a musician. Per the wiki, "when the Grimm Troupe is first summoned, he can be found playing the accordion just inside of Grimm's tent in Dirtmouth." He is sitting on a stool inside the tent's left wall, playing through the Troupe's theme as ambient music.
According to the wiki, the first conversation is pro-Ritual. Brumm encourages the Knight to find Flames for the Grimmchild and to follow the Ritual through to its end. He gives no hint at this stage that his stance will shift. The wiki frames this as standard Troupe recruitment dialogue: the same lines a Brumm npc in any past Ritual would have given.
The wiki specifies that Brumm remains in the tent across the early Flame collection visits. He does not follow the Knight to the Grimmkin spawn locations, and his lines stay short. The tonal shift only triggers after Grimm himself is defeated; that is the moment Brumm relocates and the second phase of his arc starts.
The middle of Brumm's arc is in Deepnest. Per the wiki, "after Grimm has been defeated, Brumm appears in Distant Village where he gives the Knight a Flame if they do not already have three Flames. He then offers to help the Knight banish the Grimm Troupe."
According to the wiki, this is the decision point. The Knight can accept the offer and follow Brumm to the Howling Cliffs for the Banishment ending, or refuse and continue the Ritual for the standard Grimm Troupe ending. Either choice locks the file into one of the two endings.
The wiki specifies that Brumm is not hostile if the Knight chooses the Ritual instead. "Should the Knight complete the Ritual instead, he explains that he bears them no hatred." The conscientious objection does not extend to a grudge; he accepts the outcome, even if it is the one he tried to prevent.
The Banishment path ends at the Lantern. Per the wiki, "Brumm is next found in the Howling Cliffs in the room of the Nightmare Lantern, where he jabs his staff into the brazier so it can be broken." His staff is the in-fiction mechanism that exposes the Lantern's core; the Knight then breaks it with the Nail.
According to the wiki, his lantern-side dialogue is the cleanest framing of his motivation. The wiki quotes: "So you followed me here, to where the Ritual began. You would join me in breaking it then? It is painful to defy the Master, but our harvest... it profanes this dark, quiet Kingdom. This once, I would see the Ritual fail. Mrmm.. Now! Let us destroy the anchor, and banish the Master. Never shall he return here again!"
The wiki specifies that breaking the Lantern triggers the Nightmare King Grimm fight; the Banishment is not a cutscene-only path. The Knight has to clear Grimm at his peak power before the Troupe actually leaves Hallownest. After the kill, the Troupe and Brumm both disappear from the game.
Make sure the Knight has all three Flames before leaving Distant Village. Per the wiki, Brumm gives the third Flame on the spot if the count is short, but the Ritual-vs-Banishment choice locks the run immediately after. In actual play, the cleanest pattern is to confirm the Flame count, pick up the free third, then either say yes to Banishment or walk away to the Master's Ritual instead.
Brumm's Dream Nail line is the cleanest summary of his entire arc. Per the wiki, Dream Nailing him returns a single line aimed at the Master:
According to the wiki, the line reframes the Banishment as an act of liberation rather than betrayal. Brumm is not turning on Grimm; he believes Grimm is also trapped by the cycle and that breaking the Lantern frees both of them. The wiki notes this is the in-fiction reason "Brumm bears them no hatred" if the Knight picks the Ritual instead.
The wiki specifies the line is available at every one of Brumm's three locations (tent, Distant Village, Lantern). The phrasing does not change between visits; the position holds across his entire arc. In practice, this is the Dream Nail line that most directly inverts the typical "villain" framing of the Grimm Troupe.
The Banishment leaves a footprint in Dirtmouth. Per the wiki, "if the Grimm Troupe is banished, Brumm disappears, and an amnesic bug named Nymm appears in Dirtmouth who greatly resembles him." Nymm sits where Brumm's tent stood and has no memory of the Troupe, the Ritual, or the Lantern.
According to the wiki, Nymm functions as a quiet epilogue. He does not give a quest, does not sell anything, and does not progress any further mechanic. His dialogue is short and confused; the in-fiction implication is that breaking the Master's anchor released Brumm from the cycle and Nymm is what is left when the Troupe-binding is removed.
The wiki specifies that Nymm only spawns on the Banishment branch. Players who pick the Ritual ending never see Nymm at all; Brumm simply vanishes with the rest of the Troupe after the standard ending plays. After a few runs, this is the clearest tell that the two endings produce genuinely different game states, not just different cutscenes.
Brumm ties into the Grimm Troupe questline, the Banishment ending, and the Grimmchild Flame economy. These spokes pick up the connected threads.
Game data and screenshots adapted from hollowknight.fandom.com, used under CC BY-SA 3.0. Original content remains the property of the wiki contributors and Team Cherry.