Alright, I'm bound and determined to make the point that Nasus is not the most powerful being ever...
1. He heard pleas from summoners, these *powerful* mages that can do whatever. Not all summoners are of equal strength. Had Nasus been summoned by Kolminye or Ashram, he probably would've been handed to right away if he tried to start a fight. Low level summoners have done stupid stuff before, like the illegal summoning of Fiddlesticks, and Lee Sin's stupidity as a youth where he blew up a village. There are hundreds of summoners, not every one of them is as godlike as the rest.
2. Nasus comes from an entire race of people the same strength as himself. The only reason he is in the position of the Great Library Protector is because of his intellect, not his strength. His entire race is as strong as him, but his intelligence is was sets him apart.
3. Why are you guys basing this on how big a threat an individual is? Anivia isn't a threat? If she wanted to she could more than likely create a new ice-age and destroy all of Valoran, but she doesn't. It's not because she's weak, but because she isn't a violent individual. There's no reason for Anivia not to be at the top of this list compared to Nasus.
4. Champions like Cho'Gath and Brand have never really seemed to struggle in their binds. In my opinion Cho'Gath is waiting for something. He is an extremely powerful void creature, and with Malzahar and Kog'Maw wandering around doing their thing I imagine he's just being patient, with some greater plan in mind. Besides, as far as I'm concerned he was bound by Reginald Ashram himself. Brand on the other hand, seems to know what the Institute is up to, and is just waiting for his opportunity to wipe everyone out.
5. Didn't you see the bloopers for Season 1? Nasus clearly has a weakness for tennis balls, one that could easily lead him to his death. To big a weakness to let him hold the title as #1.
1st. Lets remember that the league WANTED RENEKTON! they wanted the mad godlike creature from another world! What they got instead was a mid combat nasus who was likely in his ult form and enraged with Renekton for what he is doing.
So not only were the summoners suprised because they got the wrong one but he was also pretty darn mad. Instead they got a creature of untold power rampaging through the institute. They were probably a bit shocked! Not to mention this was early in LoL lore sooo...dont know.
2nd. These are more or less a response to ur points. 2 him and renekton were indeed the strongest of their race. One was the protector(renekton) and one was the teacher/librarian(nasus). They were leaders in positions of power because they were put in such influential positions.
3rd. I agree more or less.
4th. Yes the void is definatly waiting. For what is the only question. Brand is frustrating for me. His lore seems soooooooo half assed. This ancient eternal being of destruction and vengence is overpowered by 1 summoner, garen and lux? I call BS.
5th. It is wise not to throw away ur argument by making a trolly joke at the end.