Ragra, Spirit of Suffering

So I've been thinking of some new champion concepts, and I came up with one I really liked. This'll have 2 parts, Gameplay and Lore. I'll start with lore. _Long ago, a mysterious isle appeared. No one knew where it came from or what it's purpose was, or even how long it'd been there. It had a horrifying and ghastly look to it, and no one dared to even go near it. However, the Noxians were masters of war, and they feared nothing. The Noxians took great interest in this isle, and had assembled a team of 4 incredibly skilled warriors. At first they used them for things like spying, assassinations on V.I.Ps, a trump card during war, and many other things. They were considered the best of the best. However, when mysterious things began to pop up, believed to be originating from the Isle, the Noxians decided it was time to use the team for something more dangerous. They were ordered to investigate the eerie isle, scout the area, make a map of the area, and if they found anything of interest, to report back to command with it. The team's leader, Ragra, was a fearsome brawler, the best in all of Noxus. He was undefeated, not even the most skilled warriors in Noxus could defeat him. Ragra was eager to enter the Isle, claiming it called to him. The rest of the team were reluctant, they felt great evil emanating from the Isle. Eventually, the team decided to leave the Isle, they would not take the risk. Ragra called them cowards and entered alone. The team returned to Noxus, and, weeks after, no contact was established with the young Ragra. After a month, he was presumed dead. As if out of nowhere, a day after he was presumed dead, he returned. His armor had been turned black, and he wore a mask that he refused to take off. The team had grown close after many years of serving together, and so they were happy that Ragra had returned to them. But something about him was different. As one of his teammates stated: ''He had become something else, he used to talk, laugh, smile and be happy. Now...he is a husk. He never takes off that damn mask, and constantly covers up his left arm. His fighting changed too, once he had honor, now...It's safe to say, he has become a monster.'' Eventually, Ragra was exiled from Noxus after killing a Noxian general for ordering him to spare a Demacian soldier so that he could be interrogated. Angered, one of his teammates went looking for him. She never returned to Noxus. Some believe she stayed with Ragra, some believe Ragra killed her. Who can say. Some report seeing a man with blackened armor and a black mask with one green eye at mysterious places, like graves and places plagued by constant violence and suffering. Some believe it may be the long-lost spirit of Ragra, or perhaps what Ragra had become. Soon people started to name him Ragra, the Spirit of Suffering. _

So his appearence would be like that of Underworld TF, with blackened plate armor, a dark green cloak, long, tattered black hair with green tips and a black mask with one eerie, green eye. Hiding under his tattered cloak is his ghastly green arm, which he uses for the majority of his attacks. He is a fast, up close brawler who uses his fists as weapons. Now, for his skills:

Passive: Touch of Agony Ragra's attacks inflict a poison that stacks up to 4 times. (damage would be mediocre at one stack, and do the same damage as Teemo's poison at 4 stacks.) Upon a 5th consecutive attack, the poison will explode, doing damage and slowing the enemy. The effect cannot happen again on the same target for the next 2 seconds.

Q: Death Grip Ragra dashes forward. If Ragra comes in contact with an enemy Champion, he grabs them by the throat. After 0.5 seconds, his hand explodes, doing damage. (Enemy is airborne during the 0.5 seconds. Causes 1 stack of Touch of Agony.)

W: Dark Intent Ragra throws down 5 small runes that create a field that slows enemies. During the first 2 seconds the field is up, Ragra can dash to it. Lasts 4 seconds.

E: Malice Ragra dashes to target enemy Champion and does 3 quick punches. After the three punches, Ragra can jump back a short distance. (Causes 3 stacks of Touch of Agony)

R: Vortex of Pain Ragra punches the ground and creates a vortex, pulling in all enemies within it's radius. After 1 second, the vortex explodes, dealing large amounts of damage to everyone in the radius of the vortex and stunning them. Also creates a field that gives all allies increased movement speed that lasts for 3 seconds.

I imagine he would be best Mid and Top, perhaps Jungle, because he has great mobility and damage, but very low defense. I've always wanted a fast, strong brawler that uses his ACTUAL fists (Screw VI and her ''fists'') as a Champion. I appreciate any suggestions or feedback you guys can give me to improve his skillset or lore! (without twisting his general concept though plz.)