Which demon was killed by Rama during Vishvamitra's sacrifice? Subahu was the demon Rama killed during the sage's sacrifice.
Vishvamitra asked King Dasharatha to send Rama and Lakshmana to protect his yajna, which rakshasas repeatedly disrupted by raining flesh and blood onto the sacred fire. Rama stood guard while Vishvamitra performed the ritual.
On the final day, Subahu and his brother Maricha attacked. Rama struck Maricha with a Manavastra, sending him far away, while Subahu was killed by Rama. The sacrifice was then completed successfully.
A common mix-up is Maricha, who survived this encounter and later became the golden deer used in Sita's abduction. Kumbhakarna and Ravana belong to later episodes of the Lanka war, not Vishvamitra's sacrifice.