Asphyxia (クシナダの楔 Kushinada no Kusabi, Kushinada’s Lynchpin) is a stage first appearing in BlazBlue: Chronophantasma.
It is a hidden dungeon underneath the 8th Hierarchical City of Wadatsumi where Tenjō Amanohokosaka has hidden Kushinada’s Lynchpin along with the Phoenix Wing: Rettenjō.
In the “Fetal Movement” version of the stage the Lynchpin can be seen as activated.