Don't they look cool? They're so cool that they live very very long lives. They have psychic abilities (as seen by the Farseer conjuring up an Eldrich Storm) and have a semi-God. See that dude on fire behind? He's a remnant of Khaine, the God of War in said universe.
There is this excerpt from one of the many books that just portrays this particular race best:
Eldrad is the greatest among us. He is the sun which eclipses the light of our stars. He is Ulthwé and the fate of our kind rests in his hands. His eyes are the keenest, no detail goes unnoticed. Four thousand runes can he cast, guiding our path through torment and war, death and salvation. He is the pathfinder, the seeker, the true guide. Even your race has trembled before his might, though you may not have known it. It was he who guided us to the Ork known as Ghazghkull, and commanded us to steer his path to your world of Armageddon. Ten thousand Eldar lives would have been lost if he had not done so. What sacrifice is a million humans for such a cause?
He knows your affairs better than you do yourself. He warned that weakling seer you call Emperor of the treachery of Horus and the strife which would engulf us, just as it engulfed the rest of the galaxy, but your arrogance deafened you to his words. Your stupidity almost destroyed the galaxy, yet you never knew how close the forces of light were to our ultimate defeat. He saw the Great Devourer and warned our kin on Iyanden, even before they had neared our galaxy.
To him all futures are laid out, just as your crude implements of torture are laid out on the cold metal of that shelf. You say we are random and capricious, we say you are vulgar and idiotic. Some of you call us your enemies. All races are our enemy in time. Some of you call us your allies. You are not allies, any more than a butcher’s knife is his ally. You are tools, nothing more. To be used and expended to protect our race, that is your fate.
Your kind think you are so magnificent, yet even now, at the nadir of our power, we can manipulate you, turn you to our ends, as easily as you might pull a trigger and fire a gun. Our time will come again, Eldrad has promised us. Once more you upstart Mon-keigh [subject spits] shall kneel before our power! This time we will not be so lenient! We will exterminate you, every world, every vessel, every one of you! Eldrad has seen the stars stained red with your blood, and it pleases him!
You think us weak, but we will be your doom, children of Earth.
Cool no?? Sadly said farseer Eldrad died in some war some time back. Just to further explain on why it's actually OKAY for a million humans to die to save ten thousand Eldar lives, is due tot eh fact that in this universe of theirs, humans occupy planets from one end to the other. There are trillions of planets fully inhabited by humans. The Eldar race on the other hand, are so few in number it's like trying to compare one pebble against the number of sand in the world. Even then this comparison isn't fair. Moving on, other sayings from Eldrad himself include:
"What do humans know of our pain? We have sung songs of lament since before your ancestors crawled on their bellies from the sea."
"Even the stars themselves once lived and died at our command, and yet you still oppose our will?"
Okay I'm just bored and have nothing to do so this post shall suffice as an "update".
