Yasei no Last Boss ga Arawareta!

A former MMO player finds themselves reborn as Lufas Maphaahl, the Black-Winged Tyrant, after being released from a long-sealed fate. This entity, once defeated 200 years ago, is credited with unleashing death-bringing monsters and is remembered as a figure of fear. Now inhabiting the form of this dreaded historical figure, they must navigate a hostile world seeking their destruction while trying to understand the reason for their revival.