Spoiler: At one point, the Dark Seldarine was also known as a rock band.
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3e Faiths and Pantheons page 112: illustration by Ben Templesmith.

Spoiler: Beholders regurgitate their preys as gibbering mouthers. Those later develop levitation and eye rays. Eventually, one voice silences the others, all but ten of the eyes merge together, and the oozing flesh begins to solidify. The creature spends a long time altering the details of its form, until it convinces itself that it achieved perfection. Unimpaired, this process results in a new beholder. However, mature beholders typically maim and poison developing ones so they become lesser beholder-kin.
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4e Monster Manual page 126: gibbering mouther, gibbering abomination and gibbering orb.
5e Monster Manual page 28: beholder.