Hellfire Egg

Hellfire Egg never had a drop rate. It belongs to the Easter 2025 event (Eon 1-45), made by rocca108, and the Sol's RNG Wiki says it came from a special egg, the Hellishfire Egg, rather than from the roll button. Because the data carries no rarity number, any rolls-per-copy estimate would be invented, so the honest summary is that it was an egg reward and it is no longer available now that the event has ended.

It is one of the nine auras tied to the Biome Eggs, the same set that produced Glitched Egg. The wiki describes the player kneeling on top of an oversized Hellishfire Egg that spews flames, with fire circling around the egg and the player engulfed in flames. The font is Rye, and the aura was added on May 2nd, 2025.

If you are comparing the Hell theme across the game, HellFire is the regular roll that lives in the Hell biome, while Hellfire Egg is only a collectible record of the event. Treat them as different entries even though the names look nearly identical.