As a species we had hoped that we weren’t the only ones in the universe. After the invasion had wiped out 75 % of the population of earth, we begun to wish that we were. But then strange happenings were being reported. The stories of magic, myths, and monsters we would tell around campfires weren’t just stories to tell in the dark. -- LatinoThor45
There was a time when we were excited that the visitors came. They came with promises. They came with much fanfare by those who believed that Aliens were going to come and fix everything. They also came with diseases that spread quickly and killed slowly. The denialists said it wasn't aliens, that it wasn't a real disease. They even refused to take actions that would prevent spread.
Three quarters of the population died. The visitors tried to help, but again the denialists insisted on preventing and refusing the aid. They also denied the association with their actions and the death count. They were right about the side-effects... sort of. In that they were right about there being side-effects. Psionic side-effects.
Belief is a powerful thing. Especially in survivors who had the subconscious power to make their imaginations reality. For the beginning, there were a great many ghost sightings. Then the walls between realities started to thin. Ghoulies and ghosties were just the beginning. Cryptids sprang out of nowhere. As well as many other creatures, one of which had very big feet.