Art by John B. (upper right)
John B. was a Human child living on Omicron Theta who painted a picture of the Crystalline Entity attacking his home. Unlike the other three surviving paintings of the attack, John's painting depicted the feeding beam of the entity as it swept across the landscape. Doctor Noonien Soong hung this portrait in his laboratory. (TNG: "Datalore")
This character was only mentioned in writing.