Once a thief, now ultimate is bad ass
What would have happened if the world's greatest master thief was isekai eyed or teleported into another world, only just to be treated like trash and get betrayed by his party, only to be left to die or to defend himself. Tree that had power. From him once becoming a weakling, now becoming the most powerful as an OP ultimate badass. With the power of a system known as the Xbox system within him, AN.
This crossover is going to be a multi crossover of Lupin the 3rd x Even Given the Worthless "Appraiser" Class, I'm Actually the Strongest x solo leveling x other anime and cartoons, comics and manga, or light novel.