Schematic diagram of the outflow ejected from the circum-CO disk evolving in the AGN disk. (1) The asymptotically isotropic outflow interacts with the AGN disk gas to form a shocked shell; the shell expands to break the AGN disk and punches a cavity. (2) Outflow persistently pushes the ringlike shell along the AGN disk on CO accretion timescale, then the shell undergoes a momentum conservation snowplow phase. (3) After the shell becomes transonic, the surrounding gas instead resumes refilling the low-density cavity. The whole evolution processes proceed circularly.