The monsters have magic capabilities. I'm sure they created an artificial light source. It's also subsidized by glowing crystals growing on the mountain's ceiling.. There are also a few places in the Undeground where light shines through from the surface. In Asgore's garden, In the flower patch you fall into, At the Barrier, etc.
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Iso
Feb 04, 2016 at 01:19AM EST in reply to