An Endless Ember is a perpetually burning coal. Endless Embers are shaped like briquettes. A running joke (?) on the show is that they are radioactive, as most real life rocks that constantly emit heat are.
One was used as a stove on the Prince Alexander’s dining car. When the Red Zephyr knocked this car off the train, flipping it over, the ember set fire to most everything inside. The people inside were unable to escape, as the doors were jammed shut. Lye Lychen and the Bell Metal Band later salvaged it from the crashed car. As it was dangerous, they had to contain it within a Shape Knight helmet; of course, Lyke soon put it right in his bag, next to the dormant god, also harmful.[1]
In Episode 27, Lyke used the Endless Ember in his second desperate attempt at a ritual to prevent Virtue Mondegreen from taking the power of the Perpetual Oratorio into herself, and to trap the Oratorio in a pocket dimension. Unfortunately, it exploded, burning his hands horribly.[2]
On her visit to the Bridge Cathedral, Pickman noted several Endless Embers in the furnace of Fire Alight. The Bridge Cathedral's scrip was made of cold chips of Endless Embers as well.[3]
During the Carnival of Moted Light in Blackwick, Dyre Ode had a vial of "undying ember" for sale, which might or might not have been intended to be a related substance.[4]
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