I Became a God by Pretending to Be an Old Friend

My name is An Ge, a librarian at the bottom of the Magic Academy. My daily routine is "Please keep quiet." Until the academy was swallowed by the abyss, and the voice in my head exploded: High-dimensional crisis detected! The hero playing system is activated! [Novice mission: Play as 'Fire Bearer' Adam, reward: Ability Seed·Purifying Fire! So, in front of everyone's horrified eyes, I, the good-for-nothing administrator, was clad in a golden phantom of flame! Step into the restricted area and purify everything! All the geniuses in the hospital were shocked! But that's just the beginning... [Play as 'City Builder' Noah and gain the ability: Basic Structure Force Field! [Play as 'Dragon Slayer' Siegfried and gain the ability: Wild Fighting Will! The problem is, every time I play, an old acquaintance from thousands of years ago seems to be awakened... A certain witch sage who once destroyed a country gritted his teeth: "Angotine... I finally found you, you liar!" Me? Who is Angotigne? And why is this big guy looking for me with murderous intent? !