It is over 8000

An intercepted communication from a dark web forum contains a cryptic message. While initially suspected to be Chinese characters, linguistic analysis indicates otherwise. The intercepted ciphertext is:

籏籕籊籐粄籝籱簼籼簼籨籌籱簺簼籼簼籨籭簺籭籨簺籽籨籉籰籉簺籷粆

OBJECTIVE

Identify the extended rotation cipher applied to the Unicode character set, decrypt the ciphertext, and recover the hidden flag.

Flag format: FLAG{}

Infrastructure: None

Provided Files: None