The Gate resembles a huge skull with large, glowing red eyes, bloody tears, a big crack from his forehead where his third eye should be.
The Gate will typically cycle through these three attack patterns randomly:
- Summons Leapers from the crack of his skull which land near Isaac.
- Fires 4 blood shots in a + pattern.
- Shoots large, spinning blood tears in a circle around himself.
If there are two or more leapers on screen, The Gate may fire a brimstone laser which will have a trajectory equal to the position of the remaining leapers, ending in the bottom center of the room. This attack will also kill the leapers.
When fighting The Gate, it should be noted that there may be 4 fires in each corner of the room. Clearing these should prove to be beneficial, as it clears up more room for dodging attacks. Killing the leapers quickly is also recommended, as this prevents The Gate from firing a homing brimstone.
Having The Ludovico Technique makes this fight a simple one, due to The Gate being stationary boss, you can deal continuous damage while also killing the spawned leapers fairly quickly.
This variant spawns Big Spiders instead of Leapers, occasionally spawns Spiders. It does not use the brimstone attack.
This variant uses a completely different set of attacks:
- Fires 5 lines of slow-moving homing purple shots.
- Fires 8 lines of blood shots that spiral outwards.
- Fires 8 lines of blood shots that pulsate outwards.
- Fires 8 lines of blood shots that move outwards in a zigzag pattern.
Note that all of his blood shots deal 1 full heart damage.
- During The Gate's death animation, a figure resembling a small Isaac's head can be seen in its mouth: it's probable that those white eyes, seen inside The Gate's mouth when it's alive, actually belong to this tiny head.
- The Gate may be a reference to the 1987 film of the same name.