From Halopedia, the Halo wiki
Kelorism is some form of philosophy (perhaps political or religious) unique to the planet Mamore. Their symbol is a cross in a circle, and is sometimes tattooed by Kelorists. Their use of the cross suggests it may be a Christian denomination. The Kelor is another name for Moringa Oleifera, which is used for herbal cures in Indonesia. There is an Indonesian proverb, "The world is not as wide as Kelor leaves.", a reference to the many uses the leaf can be put to. The proverb is used to suggest optimism in the face of struggle, as in "There are still plenty of fish in the sea."
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