Beta XII - A entity The Beta XII - A entity was a noncorporeal being composed of pure energy first encountered on Beta XII - A . Appearance and abilities . The entity appeared as a small , circular pattern of multiple swirling lights in different colors , although it became red in hue and emitted a high - pitched wail when " feeding " . The entity fed on the emotions of hatred , anger , and primitive predatory instincts exhibited by humanoid s in close proximity to it . If these emotions were not present , the entity was capable of creating conditions to spawn such feelings . The entity could control the instantaneous transmutation of matter from one form to another , turning everyday objects into weapon s and sealing bulkhead s on a whim . It could pass through solid objects at will , teleport from one location to the next , and influence the thoughts of others . It could heal a humanoid ' s mortal wounds , and could even alter a person ' s memories so that they remembered fictional family members and events that never existed . The entity appeared unable to communicate in any fashion understandable to a humanoid . Although its motives and nature were not wholly known , it lacked the same ethical standards of most humanoids and largely acted in a malignant fashion . Its only weakness appeared to be exposure to emotions of humor , good nature , and friendship ; it was particularly susceptible to laughter . History . In 2268 , the entity created conditions by which a Federation starship , the , came into conflict with a Klingon vessel . The entity began fostering anger and hatred between the two crews , making the crew of the " Enterprise " believe the Klingons had wiped out a fictional Federation colony . The Klingons suffered an explosion on their ship which killed most of the crew , leading them to believe they had been the victims of a Federation sneak attack . Hence , a great deal of enmity already existed between the two crews when the Klingon survivors were taken aboard the " Enterprise " . The entity then began work in earnest . First , the entity sealed bulkheads across the " Enterprise " , trapping many crewmen below decks so that the number of Klingon and Starfleet combatants could be equal . Then , it sent the starship on a mad chase through the galaxy at maximum speed , with no way to change course or stop the ship . Finally , it created primitive weapons , such as swords , from everyday objects , to make the conflict between the combatants more brutal . The outcome was predictable . The Klingons immediately attempted a savage takeover of the " Enterprise " , with Starfleet personnel fighting fiercely for their ship . Casualties on both sides soon found themselves miraculously healed to fight again . One Starfleet crewman took to wandering the corridors in a murderous or lust - filled haze , assaulting the enemy at will in a misguided act of vengeance . Through all of this , the entity roamed the ship to feed on each act of hatred and violence . It was only through a supreme struggle of will that members of the Starfleet crew were able to deduce the involvement of the " third party " entity and what it was doing . They realized it would be even more of a struggle to convince the Klingons to lay down their arms and join them in " laughing " the entity off the ship . Through careful convincing , however , the Klingons eventually did just that , and the entity , confused and starved , fled into the depths of space barely saving the ship . ( ) Appendices . Background information . The entity ' s special visual effects were designed by Mike Minor , on which he noted , " " There was a little alien whirlagig that fed on anger . The original idea was to rig a puppet , but there wasn ' t enough time on the set , so I suggested an effect with a child ' s pinwheel that could be ' burned into ' the footage in post - production . I put some jewels and little flashing sequins on it so it would sparkle and Van der Veer added some color effects . The shot was double printed by flopping the film so it wouldn ' t seem to spin in one direction . " " ( " " , issue 25 , p . 61 ) Apocrypha . The entity made an appearance in the " Q Continuum " book trilogy by Greg Cox , where Q referred to it as ( * ) – whether this unpronounceable glyph was its true name or if Q simply made it up to make the entity seem even more alien was never truly made clear . The novel states that the entity was the cause of a war that rendered Sargon ' s planet uninhabitable , and that it and Gorgan , the " God " of Sha Ka Ree , and 0 engaged the Q Continuum in battle , with it and Gorgan escaping via a black hole after their comrades were defeated . The entity also appeared in " Night of the Vulture " , a short story also written by Cox , featured in " Tales of the Dominion War " . The entity delighted in the carnage of the Dominion War but unwittingly saved the Federation and Klingons when its machinations killed the crew of a Dominion ship en route to Terok Nor with the codes that would deactivate the minefield guarding the Bajoran wormhole . The entity then became permanently imprisoned in a spatial rift .