Source: Lost Omens World Guide, pg(s). 20
The aeon orbs are powerful magical crystals that emit a form of radiation that supercharges plant growth in a 15-mile radius around them. The god Aroden took them from the Darklands in the first decades after he raised the Isle of Kortos from the seafloor, and placed them into the Aeon Towers located on Kortos and the nearby Isle of Erran. They enhanced agriculture throughout the islands for millennia until Aroden's death at the end of the Age of Enthronement. Since then, their divine magic has begun to fade, leaving the aeon orbs and towers vulnerable.