As seen in Star Wars: Return on the Jedi, Ewoks are the indigenous tribal species of natives that live on the forest moon of Endor. While they may look as cute and cuddly as teddy bears, they are a formidable race, using a variety of weapons and traps (no matter how crude or primitive) to great effect while assisting the Rebel Alliance during the Battle of Endor. However, to hear a retired ex-Stormtrooper tell it in Star Wars Tales #14, the Ewoks were more than just formidable... they were frightening, deceptively horrific, and terrifying creatures.
The Ewok tribes provided support to the Rebel Alliance as they sought to infiltrate the Imperial base on Endor that housed a large shield generator protecting the Empire's second Death Star. Using slingshots, spears, and swinging logs, the Rebel Alliance and Ewoks won the day, taking down the generator and allowing Rebel forces above the destroy the second Death Star. Combined with the deaths of Darth Vader and the Emperor, and the Rebellion had a decisive victory on their hands that led to the eventual end of the Galactic Civil War. Without the Ewok's help, it might have never happened. However, the Ewoks apparently did much more than was seen on the screen. Much, much, more.
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The story of the Ewok's capacity for terror and fear is entitled Apocalypse Endor, written by Christian Read with art by Clayton Henry, found in the fourteenth issue of Dark Horse's Star Wars Tales anthology series. In the issue, the war is over and an ex-imperial stormtrooper is reminiscing at a bar about his glory days in service to the Empire. Eventually, other patrons ask how it was that the Empire got its butt kicked by a bunch of cute and cuddly Ewoks with pointy sticks and a happy song. Angered and somewhat shaken by the memories of the tale he's about to share, the ex-trooper counters that there was plenty that wasn't shown on the holo-vids.
Apocalypse Endor reveals that the ex-trooper was part of the initial Imperial force that was sent to the forest moon. All they knew at the time was that there was a tribal, arboreal culture living on the surface, but they paid little attention. Who could stand against the Empire, let alone seemingly feeble and indigenous tribes? Upon first contact, the curious Ewoks approached the imperial squads with a little apprehension, offering flowers. However, unknowing the purpose of the blasters in the trooper's hands, they put the flowers in the barrels, causing the troopers to believe it was an attempt at sabotage, and they opened fire upon the Ewoks. It was a terrible mistake that would haunt the Imperials until the day of the Rebellion's victory.
The Ewoks sought vengeance after that first meeting, picking off the troopers one by one from the trees above, pulling them up with ropes by their necks, separating them from their fellow troopers, only to leave their remains behind for the squads to find later. All throughout their hunt and every night, they would also consistently beat foreboding drums in the dark, setting all of the troopers on edge, driving them to madness. Some troopers just couldn't handle the constant fear and noise, breaking completely. It's exactly what the tribes wanted.
Even when Darth Vader himself arrived with additional forces, the Ewoks never let up their campaign of terror on the stormtroopers and was only helped with the arrival of the Rebel troops in Return of the Jedi. The Ewoks became such a source of terror to the troopers, that many of them, including the narrator, saw it as a relief when they were eventually arrested by the Rebellion and taken away from the moon that was filled with the furry nightmares.
As the ex-trooper narrating finishes his story, he says that while he never got a good night's sleep on Endor, he does take comfort in the fact the Ewoks were destroyed as a result of the second Death Star's destruction, with 30 billion tonnes of metal and wreckage falling on the moon's surface and killing them all. However, another patron at the bar corrects him, saying the majority of the debris burned up in the atmosphere and that the Rebellion took care of the rest, keeping the Ewoks safe, bringing disappointment to the ex-trooper's ears. So the next time a Star Wars fan watches Return of the Jedi, and wishes that Ewoks were real, that's fine and dandy. Just remember that there is something underneath all that cute and fuzziness if you ever got on its bad side. Be afraid. Be very afraid.