40K I will put my money on Necrons, they will handle the most job. Lets see-Machines made out of near-indestructable metal, who can and will teleport when damaged, carry hand mounted railguns, if i'm correct, they also have fully automatic ones. And they can transform life force(something soul like) into WMDs who are quite powerful. Are backed up by ''Things'' who are more powerful tan god and they have ultimate control over material universe. Oh and they also have a weapon which can counter halo. A hollow planet with map inside(forgot the name), and from that map, just by touching a star, you can make it go supernova. Oh and they also have complete immunity against-Halo bullets,halo effect and Pretty sure that they can kill Precursors since forerunners already killed them(that proves that they aren't invincible). Overall precursors shouldn't be included because we barely know anything about them. Oh and lets not forget about [url=http://warhammer40k.wikia.com/wiki/Nightbringer]This badass[/url] Also, Necron lords can resurrect other necrons almost infinite number of times. And then there are these who badasses -[url=http://warhammer40k.wikia.com/wiki/Tomb_Stalker]Tomb Stalker[/url] [url=http://warhammer40k.wikia.com/wiki/Necron_Overlord]Necron Overlord[/url]