From Halopedia, the Halo wiki
Tarjak was a gallery of petrified ancient forest on Sanghelios where two Sangheili clans fought for several cycles, isolated from the outside world. 'Crecka fought alongside the uncle of Ussa 'Xellus, where he lost one of his eyes in battle, and earned the nickname "Quillick" for his skill as a scout. The place was little-known enough for Crecka to use as a safe-word to organize a meeting between Ussa and himself.
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