• Using the egg while having empty hearts will restore the player to full health.
• Dropping the egg and shooting it will break the egg, either spawning a random item or gun, or spawning a harmless slug-like yolk creature that follows the player around until they kill it. The player will only receive an item or gun after carrying the egg through a certain amount of floors. Going through 2 consecutive floors will cause the egg to start hopping slightly and drop a or tier item or gun when broken.
• After 4 consecutive floors, the egg will start bouncing and drop an or tier item or gun when broken.
• The yolk creature can be jammed, in which case it will damage the player on contact.
• Dropping the egg into any source of fire goop will spawn an Ancient Serpent . There is a long delay before the serpent spawns; a room with active enemies may well destroy the egg before it hatches.
• Like the serpent in the Resourceful Rat's Lair, the hatched serpent must be fed to awaken it.

• Phoenix Up - If the player has [Phoenix] , summons a phoenix companion that fires at enemies.
• Two Eggs Over Easy - If the player has [The Scrambler] , its homing shots cause poison .
• Pits in the Forge don't count as sources of fire and the egg will be lost upon dropping it in.
• Dropping the egg on green fire will break the egg and no serpent will appear.
• This item will carry over to a handful of Gungeoneer pasts, excluding the Pilot's, the Hunter's and The Bullet's, and will be available as a pickup beside the Gungeoneer upon spawning instead of automatically being in their inventory.
• During a Rainbow Run , if the egg appears out of the chest, shooting the egg and breaking it will cause the yolk creature to spawn and all other items to disappear after a short period of time. The player can choose an item before they disappear.
• Saving and exiting the game prevents progress made in consequtive floors for purposes of getting loot.

Enter the Resourceful Rat's Lair for the first time.