A new hidden gem by Rocksteady Studios in "Batman: Arkham Knight" has been found in the form of an exclusive premium skin unlocked after an accomplishment.

The newly-discovered skin was spotted on a YouTube video by highly observant gamer Sean Myers. The skin features a downloadable batsuit being dubbed as Batsuit version 8.05, which sports a gold bat emblem instead of the traditional black to pay homage to the original batman costume which had yellow emblems. The suit's torso area is also slightly a darker shade compared to the default one.

Unlocking it will be a challenge as gamers will have to reach a 240 percent completion rate, which means completing the game twice, and then crossing over through a little less than half. One 100 percent completion requires gamers to find 200 Riddler trophies so that the ending will be unlocked.

The second round will then be in the New Game+ mode of "Arkham Knight," which is said to be very difficult to complete, and then going through 4/10 of it the third time around.

The Prestige Edition skin is added into the final "Season of Infamy" DLC, where Batman faces villains like Croc, Ra's, Mr Freeze and the Mad Hatter.

"Batman: Arkham Knight" is an action-adventure game that takes players through Gotham. The story revolves around Bruce Wayne's confrontation with villains like Scarecrow, The Penguing, Two-Face and Harley Quinn.

"Arkham Knight" was developed by Rocksteady Studios, who has also developed other Batman video games like "Batman: Arkham City" and "Batman: Arkham Asylum." The game is published by Rocksteady's parent company Warner Bros.

Metacritic gives "Arkham Knight" a score of 85 out of 100 based on 16 critics. User score is pegged at 6.3 out of 10 as the average of 600 ratings by gamers who have tried the game. The game is playable on Xbox One, PS4 and PC.