This indicates that the movie is available with Hindi as one of the audio tracks, often alongside the original language (in this case, Korean). Dual audio tracks are especially popular in regions where the movie's original language might not be widely understood.
For the best viewing quality (WEB-DL) and legal safety, it is recommended to use the download feature provided within the official JioHotstar or Prime Video apps, which allow for offline viewing on mobile devices. JioHotstar Alienoid - Prime Video
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