Which studio helped Studio Mir on Book Four through its companion subunit?

Studio Reve helped Studio Mir on Book Four of The Legend of Korra through its role as Mir’s companion subunit.

Studio Mir was the principal South Korean animation studio behind much of The Legend of Korra. Its work extended beyond finished animation: the studio also contributed to pre-production, storyboarding, and the series’ highly regarded martial-arts choreography.

Book Four was produced under unusual circumstances. Nickelodeon reduced the season’s budget by roughly the cost of one episode, prompting the creators to make “Remembrances,” a clip-show episode, rather than dismissing members of the production staff. Studio Mir returned for the final season and received assistance from Studio Reve.

A common mix-up is confusing Studio Reve with Studio Pierrot. Pierrot animated part of Book Two when Studio Mir was unavailable, while Studio Reve was Mir’s companion subunit associated with Book Four. The show ran for 52 chapters across four books, ending with Book Four: Balance in 2014.