1) Critical 2) Extremely critical 
Above the critical point; above critical temperature or pressure.
[adj] - (especially of fissionable material) able to sustain a chain reaction in such a manner that the rate of reaction increases
supercritical 1. Highly critical. 2. Of, pertaining to, or designating a fluid at a temperature and pressure greater than its critical temperature and pressure.
A chain reaction that grows rapidly because an average of more than one neutron from each fission reaction causes another fission reaction. An extreme example of this is the explosion of a nuclear bomb. See also: Neutron, Subcritical.
adjective (especially of fissionable material) able to sustain a chain reaction in such a manner that the rate of reaction increases
extremely critical. · pertaining to a mass of radioactive material in which the rate of a chain reaction increases with time.