The world crisis

One day earth changed some would say for the better some would say for the worse but there is no point in arguing as what has happened already took effect. Earth was invaded by monsters 10 years ago the earth went into mayhem as monsters from space dropped down and caused destruction everywhere One day a strange event appeared, people randomly gained inhuman abilities that used magic and started killing lower-level monsters and saving the world one monster at a time in its most desperate time the monsters never stopped coming and soon humans were getting pushed back but this caused the monsters to claim a whole content. Time skip 50 years ahead and humans have developed a school to teach students about monsters and how to train their abilities. The requirements to get in are almost impossible and only the best can get in even teachers where A or S grades but as they aged they got weaker although they are still very powerful and are not to be tested. Throughout these years new info was found about the earth appearing also such as the earth has started to grow rapidly about 100,000,000% bigger every 30 minutes.