First of all let me clear things up, this is a sect that has ancient practices and uses magic in the modern era where monsters from other worlds invaded ours so stop being so surprised when they show a piece of tech, second of all how on earth did mc know the third had that weapon??? he had been living on the streets as a nobody for 10 years because he quit and did not even know his brother had died till the assasins told him but he certainly did not tell him that mc's brother found a weapon called boundless 😔 and that uncle seriously left mc alone to play with all of these weapons???
fate is a steryotype that must be broken in order for a story to even be written