Javelins of Light are a mysterious weapon that appear in Fire Emblem: Three Houses.
The weapons referred to as Javelins of Light are wielded by Those Who Slither in the Dark.
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A remnant of ancient Agarthan technology, they are missiles kept in orbit that still have the capability to launch. A bombardment of Javelins of Light is powerful enough to reduce Fort Merceus to complete ruin. The people of modern Fódlan, with no understanding of such technology, view the destruction caused by Javelins of Light as the result of an unknown and terrible power.