Star Trek vs. Star Wars (and a collection of memes)

It was seeing this great artwork that first inspired my belief that Grievous should have been marketed as a bane of Clone Troopers, not a Jedi killer (which was Darth Maul's forte), if they wished to preserve the plot point of him not having any Force-sensitivity. Four Lightsabers wielded effortlessly by a cyborg is easily enough to beat the Republic's finest Clone Troopers, and because they made up about 90% of the Republic's army structure, Grievous would still be a valuable asset to the Separatists.

He could easily have been introduced via a scene where a Clone Commander recalls a night battle in a flashback where a shadowy, cloaked figure emerges to confront the Commander and his squads, giving a sinister laugh and igniting a Lightsaber, then a second, then a third, and then a fourth. The Troopers fire, but the figure deflects every blaster bolt fired its way, striding forward and spinning its Lightsabers with a murderous intent. The Commander gives the order to "Bring it down!" but it is too late as the figure leaps in amongst them, pinning down a Clone with metal talons and killing him with a Lightsaber through the head, while bisecting two others with two other blades. Another Clone draws a sidearm and fires into the figure's face, illuminating it briefly as that of a bone-armoured cyborg with reptilian eyes, but its faceplate absorbs the hit with little damage, a Lightsaber cuts off the offending Clone's blaster hand and a second impales him through the chest, even as another Clone behind the cyborg is swiftly beheaded. The figure mercilessly cuts his way through the mass of Clones, the Commander having taken a deep wound across the chest and being knocked onto his front. Agonised, the Commander can only clasp at the wound in the pain for several seconds, before he turns round and sees the cyborg standing over the butchered corpses of all his men. Desperately he claws at the ground to reach for a Thermal Detonator, even as the cyborg turns to notice he is still alive, its yellow eyes glinting in the darkness. The Commander activates the Detonator and throws it at the cyborg, but after the explosion, there are no burnt and twisted scraps of metal where it once stood - instead it has long vanished from the Commander's view, scuttling away on six insect-like limbs to fight another day.

"I alone escaped that night..."