A possible top laner?

A top lane tank bully. Operating as an in and out light bruiser who shreds tanks through stacking dots. Champion: Cohtyl Lore: Appearing of Central American Descent (Coatl meaning serpent in early Yucatan language), Cohtyl wields a sling, in his other hand he has a shield fixed to his forearm. He could be from Zaun (Possibility of someone who doesn't give Zaun a bad name ie Ekko ally?), appearing to use chemicals/incantation/disease or from Ionia using magic/spirits similar to Yorick's Omens/corruption ie Varus. Could be a thin appearance yet fierce ie Riven or a beefier but still lean appearance as he will operate as a kind of rogue.

(Passive) A multiplicative dot will apply to enemy champions with Cohtyl's spells and every second attack. 1st stack: Applies a dot that does 1.5% of the targets max hp for 2 seconds 2nd stack: Applies dot that does 2.5% of the targets max hp for 3 seconds. 3rd stack: Applies dot that does 6% of the targets max hp for 4 seconds. 4th stack: Applies dot that does 8% of the targets max hp for 5 seconds. 5th stack: Applies dot that does 8(.5 AD)% of the targets max hp for 5 seconds and slows them for 30% 6th stack: Applies dot that does 8(.5 AD)% of the targets max hp for 5 seconds and stuns the target for 2.5 seconds. (6th stack can only occur once every 8 seconds)

(Q) (85 second CD?) (Active) Cohtyl slings a projectile forward a short way, hitting the first champion struck dealing 35/45/65/85/105/125 +6% of their current hp and slowing them for 30%. (W) (1015 second CD?) (Active) Cohtyl dashes forward, silencing champions struck for 1.5 seconds and his next attack reduces the targets bonus resistances by 45% for 4 seconds. (E) (1827 second CD?) (Active) Cohtyl blinks towards a target area dealing 70/80/90/100/130 magic damage around him, if a champion is struck, Cohtyl appears behind the champion furthest from him that was damaged. (R) (80110 second CD) (Active) Cohtyl gains 15% damage reduction for 8 seconds increasing by 5% for each nearby enemy champion. For the duration, Cohtyl can break the CDR gap as well as gains 60 movement speed, doubled when moving towards enemy champions. For each stack of his passive on an enemy champion around him, Cohtyl gains 2.5% CDR. (Passive) Cohtyl gains +40% tenacity when below 40% (90 seconds CD)

Basically, the concept is a champion that can dance around tanks, beating them at their own game of slow and painful deaths. More than open to any kinds of tweaks, I consider this concept the community's because all I could hope for is this concept evolving into an actual edition to Leauge. Please, theory craft away.