There, Grimm offers the Knight to take part in the Ritual, and entrusts them with the Grimmchild. They set their tents in Dirtmouth, under the anxious looks of the local inhabitants. The Grimm Troupe enters Hallownest once the Knight has lit the abandoned Nightmare Lantern in the Howling Cliffs, placed by a dead acolyte. Once the child reaches maturation, the Nightmare King must be killed to sustain the Nightmare's Heart, and then be reborn anew. There, Grimmkin Novices, Grimmkin Masters, and Grimmkin Nightmares travel to harvest Flames of Nightmares and feed them to a Grimmchild.
They travel through dreams wherever an acolyte has set and lit a Nightmare Lantern, but are banished from it if it is destroyed. In truth, the members of the Troupe are slaves to the Nightmare's Heart, a being born from Nightmares, and tied to a perpetual Ritual to sustain it.
The known members are the Troupe Master, the charming Grimm himself, the accordion player Brumm and Divine, as well as a couple of Grimmsteeds.
Their colour theme is red, and they all wear white masks with vertical splits crossing their eyes. The Grimm Troupe are a joyous group of travelling performer bugs of various species.
