Commander in Another World

Razius woke up in the game-like world how he survived in a world with power like magic called Arts and alien-like creatures called the Sirens. The protagonist will be strong, but just like other strong characters in the world. I mean, in the game, Elite 2 Lv 90 is the end game. Look at my name... This Fanfic will be a harem. Suppose you don't like it. Please leave. I play Arknight and a bit of AzurLane. This is just Fanfic, so there will be some difference with the lore since I don't know or expert with their lore either. Also, their characteristics too. But I try my best.