Time Magic

Time Magic allows to manipulate time. It was considered nearly completely extinct at early Preimperial Era, since it is simply too dangerous. Trying to move back in time for a single day to prevent someone's death could as well end with becoming your own grandfather. They were also disastrous (but, because of gods, only local in size) paradoxes that ended up with whole communities simply erased, or by later historians discovering authentic and confirmed evidence that certain event happened in few different ways...
It was generally cut out from usage at the times of the First Empire. It locally grew during the Late Archaic period of chaos, but it was finally chopped down by supercivilizations of Ancient Era. The destruction was finished by Imperium of Karadia, that launch a purge of remaining time magicians together with various other states, while also forbidding nearly all spells. Artifacts were confiscated, books burned (despite one specimen of each book, put in the Crypt beneath the Imperial Library). Today only few easiest spells remained, for example one allowing to slow down time for a while.
Xylian Dominion tried to erase human Kingdom of Kharyth that was their archenemy until ~1200 year of Imperial Era, only to end up getting wiped out by Command AI around 2300 years earlier. Which is probably the best way to picture how using this magic ends.