The entrance to the first chamber where a jinchūriki attempts to control one's tailed beast has a sculpture of the Two-Tails' head with a switch inside its mouth, only accessible by entering head first. The chamber is designed to hold a tailed beast, in case the jinchūriki failed to master control and allow the beast to be reborn, and lock it up until a new jinchūriki comes forth. Chakra Isolation Chamber