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Battle in Disguise (変装大作戦 Hensou daisakusen?) is the twelfth Story Mode arc from Pop'n Music Lapistoria. If this arc is complete, you will receive Hatcha Metcha Party as your unlockable song. To unlock this arc, you will need to complete The Secret of the Principal's Office?, which both and To Investigate the Cause are released on August 13, 2014.
The entire translation of Battle in Disguise was done by Tumblr user abyssalnode.
Retsu and Rinka were thinking about the way to creep in the principal's office. They seem to notice Nia on the avenue...but that is not her!? It was her younger twin Toa. Retsu comes up with items to make the principal's cloak, hearing that Toa has the hobby to make clothes.