Is the OST cover shown on the booth website the final one?

This only started happening since I got the アイスブランド (Ice Brand?) weapon for フランドミナス (Flandominus?). It seems sound files for this specific weapon are missing, because as soon as he attacks, I get an error that says "Failed to load: Slash1.ogg". I recorded a video: https://i.imgur.com/InnCkbL.mp4 I tried changing language from Japanese to English and reinstalling the game, but it didn't work. As a temporary measure, I made a copy of "Slash2.ogg_" and named it "Slash1.ogg_". Then...

I have been stuck at the led's ball for a long time. The equipment should all be the best at present. But in the best-case scenario, It would only result in the ball being low HP. How can I defeat it

プレイ時間はどれくらいですか？

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