Complex sentence: All science fiction of Soviet time had to subscribe to communist ideology, or else the author could face serious consequences--from ban to publish to death penalty under Stalin or imprisonment or psychiatrical treatment under Brezhnev.
Split into simpler sentences: All science fiction of Soviet time had to subscribe to communist ideology, or else the author could face serious or fatal consequences. They could vary from ban to publish to death penalty under Stalin or imprisonment or psychiatrical treatment under Brezhnev.