Kinda late to the party. Odds are the typesetter won't read this, but in case someone else is wondering.
Often in MMOs you have event-exclusive items, items that you can only access if you play the game in certain dates, e.g. a Santa hat for playing around Christmas. More invested players often collect this crap, even if it's just cosmetic, as if creating an ingame virtual collection. The actual mechanics to obtain the items might vary from game to game, but it's clear that in Cross Reverie this was lottery-based. (Urgh, crappy gacha mechanics. That's one of the reasons I refuse Japanese MMOs are often crap.)
Well. Diablo missed that scythe from the event, and since he's invested in the game (he's the top player in his server) he was kinda bitter about it. Well, his collection won't be complete but at least he got the real deal in hands, close enough right? Getting the isekai equivalent of that will probably make it up.