The Cage is a boss that can appear:
- Leaps off-screen and tries to land in Isaac's path; predicting his movement. Leaving a small puddle of damaging Grey Creep and sending out 4-5 lines of rock waves upon landing.
- Quickly shoots 6 streams of 3-7 projectiles in a spiral pattern, similar to Mom's Heart/It Lives.
- Curls up in a ball and rolls towards Isaac, bouncing off walls and obstacles around the room.
- Spawns a grey-coloured Vis that shoots a brown-coloured Brimstone laser.
- The different colours are purely cosmetic, and it behaves exactly like a normal Vis.
- Any Vis caught in The Cage's rolling attack will be killed.
Champion Versions 
- Green: Periodically leaves puddles of Green Creep and doesn't spawn any Vis.
- Pink: Two Cages, each with 50% HP (400), replace the normal Cage. They never perform their jump attack.
The Cage as one of Delirium's forms.
- Host Hat and Pyromaniac make Isaac immune to The Cage's rock waves, since it is considered to be the same as explosions by the game.
- When The Cage jumps, there is a delay to his falling animation, causing Isaac to be hurt before the Cage falls back down.
- If Isaac is flying on Pits, The Cage can hit Isaac if it jumps towards him, and it will then be pushed back to the ground.
- It has the highest health of any boss fought before Mom's Heart.
- It is the posthumous version of Mega Fatty.
- Although the Cage is a dead version of Mega Fatty, it also bears a lot of resemblances to a giant Vis as well, since it is a fat headless body with a giant cut in its belly. Another slight nod to their resemblance is also the Cage's ability to spawn Vis with a Grey color palette and a Brown Brimstone laser.
- The stitches on the Cage's body resemble Y-shaped incisions commonly made at the start of an autopsy.
- Despite being a possible encounter before Mom, The Cage has more HP than her.
|The Binding of Isaac: Rebirth|
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