Mass extinction

The process in which huge numbers of species on a garden world die out suddenly. Divided into (from most severe to least)

• Class 10 - All life destroyed. Result of a massive cosmic collision, stellar disturbance, or planet killer weapon.
• Class 9 - All surface life (even microbial) destroyed, rare microbial life survives deep in the crust.
• Class 8 - Most life destroyed, some microbial life survives in sheltered environments.
• Class 7 - All higher life destroyed, microbial life survives.
• Class 6 - Almost all complex life destroyed, microbial life survives.
• Class 5 - Most species and groups of organisms killed.
• Class 4 - Many species and groups of organisms killed, others survive.
• Class 3 - Many species extinct, but most major groups survive.
• Class 2 - Some species extinct, many survive.
• Class 1 - Suspectible and vulnerable species die out, all others survive.