6 months ago I created a list of what I believed to the be the 10 most powerful champions (http://boards.na.leagueoflegends.com/en/c/story-art/a2ZFYXv5-laughing-fishs-top-10-most-powerful-champions-lore?show=new) Since then, however, lore has changed, new champs have been released, and I have severely increased my knowledge of League of Legends' lore. SO without further ado: Here is my updated list of Runeterra's most powerful champions.

Honorable mentions:

#10: The Cryophoenix Anivia is more than just a glorified chicken. She has seen empires rise and fall, and watched seemingly unstoppable forces fade away. She is the keeper of ice magic, and controls the power of the cold itself. Storms start and stop at her word, and each of her lifetimes heralds in a new age for the Freljord. She prefers to stay out of the affairs of humans, but corruption of the frost has forced her to intervene in the war for the Freljord.

#9: The Emperor of the Sands SHURIMA! Your emperor has returned! Azir was slain millennium ago by his slave, Xerath. But death could not contain him. Chosen for accession before his death, Azir was brought back by the blood of Sivir, his last living relative. He has the power to control the sand, and can build soldiers to do his will out of the desert itself. He has brought back the ancient magics of Shurima, and hopes to restore it to its former glory.

8: The Curator of the Sands

Much power. Very ascended. Wow. He is one of the ascended, and is the ancient guardian of Shurima. He has limited control over time and the life force of those around him, and is able to siphon their lives to strengthen his own. He is immortal, and has gathered thousands of years worth of experience.

7: The Magus Ascendant

His power is SHOCKING! Xerath is a being of pure arcane energy. The product of a failed accession, Xerath is no longer bound by flesh. Once a slave, Xerath orchestrated the downfall of Shurima, and ended the reign of Azir. Things were not all lollipops and giggles though, as Xerath himself was captures and entombed in the process (although it did take not one, but two ascended to beat him, and even then they only managed to temporarily contain him). But after thousands of years, Xerath has returned to this world. He. Will. Be. Free.

6: The Terror of the Void

Contrary to popular belief, Cho'Gath does not live under a bed, he comes from the Void. Cho'Gath is one of the only creatures to summon himself into this world. He hijacked the Leagues summoner magic and brought himself into Runeterra. Thinking they had trapped the monster, they put him to work fighting in the league. They came to realize later that Cho'Gath allowed himself to be captured, and only remains as it gives him an easy source of prey. He is a vile creature who grows in strength and power as he eats. and he eats A LOT! Cho'Gath is no mere beast though. Underneath his gruesome and violent nature lies a cunning and deadly mind.

5: The Prophet of the Void

Warning: Fighting Malzahar might will result in Space Aids. Prophet of the Void has a connection to a being on the other side of the rift. He can create portals to the void, and can summon horrors to do his bidding. Given his way, he would bring monsters into this world that would consume all light and life. If he is not stopped, there will but nothing left but darkness.
#4: The River King There is something fishy about Tahm. Tahm Kench is a demon with an insatiable appetite. He lures people to him by promising them their deepest desires, only to feed on their anguish as everything they love perishes. Two-coats will give you exactly what you asked him for, but your journey will be met with only despair. Throughout history Tahm Kench has swam, singing his sickly-sweet song and preying on the foolish and greedy. His strength is limited only by the greed of his victims. And there will always be somebody greedy for him to feed off of. #3: The Darkin Blade His work is no hack job. One of the last of an ancient species known as Darkin, Aatrox is a fearsome and deadly creature. Aatrox has been seen at most of Runeterra's most bloody battles since before written history. He thrives off of violence, and feeds the fires of war. Nations have risen and fallen by his hand, and he continues to reshape man's morality like putty. His symbol is even found by the cranks on summoners rift, suggested he may have caused the rift in the first place. As long as men are violent, Aatrox will continue to thrive.
#2: The Deathsinger What is that sound? It's the pounding of creation's hammer on the anvil of time. The Deathsinger is arguably most deadly being in the league (he was ranked number one on my old list). Karthus holds the key between life and death. He has formed an ever growing army of the souls of the dead. Even if you manage to destroy one of his soldiers, he simply brings their souls back to this world. He is the only known wielder of oblivion, which is the essence of death itself. But that is not all: Karthus is a master manipulator. Despite the horror of his ideals, he manages to convince those to willingly give themselves to death. Every victory for you means nothing while The Deathsinger lives, but every victory for him makes his armies grow larger. So why is he no longer number one? There is one champion that I think could end his reign:

1: The Wandering Caretaker

The Wandering Caretaker is B-B-B-B-Bard to the bone. Bard is a celestial caretaker that exist outside of space and time. He ensures that the universe continues on its correct track. The thought process of this strange creature is certainly beyond us. We know only that he sees what was and what will be, and knows how the actions of an individual will effect the world for thousands of years to come. Why is he at the top of a list of gold-like beings? Because all of the previous champions only exist because Bard allowed it to be so. He could go back and kill them as babies, and could have ended their bloodline long before they were conceived. But for one reason or another, he has determined that none of the previous champions are worth stopping. Others may be strong, but Bard has transcended the need for strength.