Saint Anthony's Fire was essentially ergot poisoning, and this toxin was produced by fungi infecting cereals like rye.
If ingested carelessly, it could lead to severe consequences.
This was also the reason why Roger, whenever he returned to his Wooden Castle, fell ill, and his health somewhat improved whenever he left.
Though the disease was not complicated to treat, merely requiring antifungal medication, it was almost non-existent in modern times.
But in the medieval period, it was quite deadly.
Usually, this disease affected peasants more often, as nobles seldom ate rye.
However, as a newly established noble family, Roger's family had recently encountered financial difficulties, which forced them also to start consuming rye due to their tight budget.
Moreover, Roger's wife was concerned about losing face if other nobles learned of this, leading to ridicule, so she even had a maid secretly buy it from a distant town.
