A Basilisk's egg was a simple chicken egg hatched under a toad, thus breeding the deadly King of Serpents. This method was first discovered by Herpo the Foul and was banned since Medieval times. The practice could be easily hidden when the Department for the Regulation and Control of Magical Creatures came to check, by simply removing the egg from the toad. The presence of a full moon could induce Basilisk eggs to hatch early if given certain other circumstances.

The Ministry of Magic said that all chicken coops in the wizarding world would be subject to police inspection to thwart Basilisk breeding.

Alastor Moody believed, in paranoia, that one of his birthday presents was a cleverly disguised Basilisk egg and smashed it apart before realizing it was a carriage clock.

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The Basilisk tongue was a forked muscular organ in the mouth of Basilisks, responsible for their sense of smell and taste simultaneously.

Basilisk tongues could be used as an additive in confectionery; Honeydukes' Liquorice Wands were free from Basilisk tongues, according to the label.