[Champion Concept] Sui, the Cryomaster

High up in the cold depths of Freljord, a tiny tribe barely survives the constant pounding of the snow and ice. The Cryorian Tribesmen are a docile people, they only house a couple hundred cryomancers, people who can manipulate the ice. But it takes all their strength to hold the Freljord's unrelenting wrath at bay. That is, until Sui was born. At the age of 4, Sui mastered the Cryorian arts, and could spontaneously create ice from thin air. At the age of 10, Sui was able to stop the Freljord's storm from damaging the tribe by himself. Sui grew up to be the very first proclaimed Cryomaster, and has led the Cryorian Tribe's survival for as long as he could remember. Being a charismatic leader, he was loved by everyone. Equipped with his katana and his notable blue cloak and umbrella-like hat, Sui kept the Cryorians safe from any danger that appeared.

That was 1000 years ago

Sui is still alive today. Using his ice magic, he has preserved his body in ice, allowing him to live forever and never age. However, when Sui finally arrived in Valoran, he wasn't taken kindly. With powers comparable to a god, if not more, he was very intimating, and the fact that everything he touched froze solid didn't help his situation. Numerous times the League of Legends summoners had to appear on the scene and ask him to leave. Sui didn't know how to act in a modern society, until he discovered the League itself. A place where he could stay. He was admitted after a small demonstration, but when he was summoned for battle, he absolutely destroyed Summoner's Rift. Due to his ridiculous amount of power, he has since been required to wear a magic nulling brace over his tank top.

"Is it cold in here? Or is it just me?" -Sui

Description: Sui is a mobile fighter who excels in dealing high burst, and then sustaining his damage right after. Even though he isn't very tanky, he is still able to duel even the tankiest of champions with his unique kit of abilities.

Abilities:

Passive: Hextech Limiter: Even though he is equipped with a magic nullifying device, Sui is still powerful enough to resist it. Replacing his mana bar is his "Frost Bar" where he accumulates frost every time he makes a basic attack or casts an ability. He gains 5 frost for basic attacks and 20 frost for abilities. At 250 frost, all of Sui's abilities gain new or improved effects. At this stage, he glows blue slightly. At 600 frost, all of Sui's abilities change completely into extremely power abilities that relate to their devolved form. At this stage, mist starts flowing upwards off his body. At 900 frost, Sui deals true damage, but his frost bar drops by 10 frost every second until it is at 700. Sui's clothes turn white and he also glows the same color. While out of combat for 10 seconds, Sui loses frost at the rate of 5 per second, which escalates to 25 per second after 20 seconds.

Sui gains 1 AD and 1 AP for every 20 frost.

_Q: _ Shiverblade: Sui sheathes his sword and starts charging. During this time, he gains 10% movement speed, but cannot attack at all or cast other abilities. After a brief delay, you can recast this ability to have Sui cleave a large area in the shape of a crescent in front of him in the direction of your cursor for 80 / 130 / 160 / 190 / 240 physical damage (+0.25 per current AD and AP) and slowing all enemies by 5 / 10 / 15 / 20 / 25% +10% for every second this skill was charged, and stunning all enemies for 1 second if charged for 3 seconds. Sui must be in battle to cast this ability.

Upgraded Effect: Sui dashes towards the cursor (or enemy champion) slightly and then cleaves the area. The damage is also increased by 10%

Upgraded Q: Icy Mirror Blade: Same situation as above. After a brief delay, you can recast this ability, targetting an enemy, to blink to that target and deal physical damage to the target.

Cool down of 6 seconds after second cast.

W: Dilution: Sui draws in the liquid around him, healing him for 13 / 16 / 18 / 20 / 23% of his current frost and stealing 10 / 20 / 30 / 40 / 50% movement speed from all enemy champions around him in a 400 unit radius for 2 seconds. This ability can be cast while moving.

Upgraded Effect: Heal now additionally gives a flat heal of 30 / 50 / 70 / 100 / 120 (+0.10 per current AD and AP)

Upgraded W: Absorbing Dissolution: Heal unchanged. AoE is increased to 800 unit radius.

Cool down of 20 seconds.

_E: _ Cold Wave: Sui empowers his blade, causing his next basic attack to have 600 range and act as a skill shot with a 200 unit width and 1500 unit length. Deals 10 / 15 / 20 / 25 / 30 physical damage (+0.25 per current AD and AP) as well as your current attack and slowing the first target it hits by 50% for 2 seconds.

Upgraded effect: Length increased to 2000 units and slow increased to 75%

Upgraded E: Ice Fissure: Same effect. Sui instead slams his katana into the ground creating a vertical wave that rockets in a line and dealing the same damage and steals movement points equal to the original slow for 2 seconds.

Cool down of 15 seconds.

R: Cryorend: Sui breaks free from his limiter and begins charging. Over the next 3 seconds, all units on the map halt to a stop as Sui freezes time. (Ice also accumulates on the screen for added effect.) After time is stopped, Sui can recast the ability within the next 3 seconds to deal 75 / 80 / 100% of his frost as physical damage and consuming all his frost as well as restoring time to it's original state. This ability does not upgrade.

Range: 750 units

Cool down of 180 / 160 / 140 seconds.

Quotes

Chosen: "Oh, okay."

Joke: "So a cryomancer walks into a bar" literally walks into a bar of ice as he tells the joke "Sometimes my ice powers don't work correctly" Walks into a bar of ice "Have you ever stuck your tongue to a pole?" Walks into a bar of ice

Taunt: Whips out katana and sticks it into the ground "In all my life, I have never seen someone as stupid as you." Whips out katana and sticks it into the ground "No, I will not sooth that burn."

I'm open to nerfs and such, I'm not totally sure if he is balanced at all.. I'm leaning towards the fact that he is super overpowered right now.