Halahala

Halāhala (Sanskrit हलाहल) or kālakūṭa (Sanskrit कालकूटं, literally: 'black mass' or 'time puzzle' ) is the name of a poison (as per Hindu History) created from the sea when Devas and Asuras churned it (see Samudra manthan) in order to obtain Amrita, the nectar of immortality.
Fourteen different "ratnas" (treasures) were recovered in this exercise, mostly retained by the Deities after the Demons tried to cheat them. But before Amrita could be formed, Halāhala was produced, which started injuring both sides. As no one could bear the lethal fumes emitted by the poison, both Devas and Asuras began to collapse due to asphyxiation. They ran for help to Brahma who refused and advised them that only Shiva could help them. So both parties went to Mount Kailash and prayed to Lord Shiva for help. Shiva chose to consume the poison and thus drank it. His wife, the goddess Parvati, was alarmed, as she gripped her husband's neck with both hands in order to stop the poison, thus earning him the name Viṣakaṇṭha (the one who held poison in his (Shiva's) throat). He was later saved by the mahavidya Tara, a form of Parvati. The poison turned his throat blue like bruise. Hence, he is also known as Nīlakaṇṭha (the one with a blue throat).
In popular culture.
The second episode of Indian television show "Sacred Games" was named Halahala based on the mythological poison.
The poison (along with references to amrita) is featured in the 2021 anime television series Godzilla Singular Point.