The Host is a Monster in The Binding of Isaac: Rebirth that is commonly found on The Caves, The Catacombs, The Flooded Caves, The Depths, the Necropolis, and The Dank Depths floors. While the skull is over the red tissue, the Host is invincible. If Isaac does not damage the Host for some time, its skull will raise up to fire a tri-shot wave at Isaac, exposing its vulnerable flesh. It can only take damage when its flesh is exposed.
- The Host's variants are the Red Host, the Walking Host, and the Walking Red Host.
- The Host is invulnerable to bombs when the skull cap is down and, if it takes enough damage, it will appear crushed, grinning at Isaac.
- Hosts can spawn from skulls on The Depths, the Necropolis, the Dank Depths, and the Sheol floors.