This is a glitch was that first discovered by lobsang2 during a Randomizer race (Randomizer 2.0 seed 98003768930 mass hysteria), that resulted in a white sword being acquired.
The setup requires a 4 headed Gleeok to be in a room with water, and the ladder. Currently the exact mechanism of the glitch is not fully understood.
The general setup is to kill 2 of Gleeok's heads, then stand over the water and let 1 of the floating heads knock you away from the water so the ladder is removed. Then kill 1 of the remaining heads while not standing on water. This sets up a weird state and the next time the ladder is activated, an extra sprite appears under it. Killing the sprite while standing in the middle of the ladder will spawn the white sword for a very short time, but it can be collected.