the "ostium flagitii" , known as the infamy door , is an ancient relic . the first documents about it come from Middle Ages , but it seems to be older.
This is a diabolical object that musten't be absolutely utilized and it shoulden't come in wrong hands. Unfortunately the relic's functioning is really simple : it can make an infamous killer travel across the time , if has really bad intents .
if he only thinks to kill someone important in the past before he had the opportunity to do something big for human being, something generous for humanity , something good. then the tentacles open to him , and he can take the "ostium flagitii" if he take the chance , it will be immediately trown in the appropriate time , and in the apporpriate moment to damn his soul for eternity. no one has come back . all the history will change , and anyone could remember how the world was.
we have trails that this relic were used in the past ,Mahatma Gandhi ,J.F. Kennedy , Martin Luther King , and others benefactor of humanity. Someone thinks that this relic is even related with Jesus's death...