Illusory Meadow

The Illusory Meadow is a strange underground garden surrounding the Venom Ruins. It is likely that the whole place is some sort of illusion, given the name and the unlikelihood of plants cultivating underground. The entire meadow is full of deadly monsters.

Trivia
A piano arrangement of the soundtrack used for the Illusory Meadow, The Grassy Plains of Illusion, appears on Twelve Doors, a tribute album to composer Noriyuki Iwadare.