Champion Concept

Goal: Make an awesome hybrid dual-wielding champion.

Brief Lore: An intelligent dual-wielding mercenary/assassin who has a knack for finding weakness. He dedicated his life to killing Malzahar for sacrificing his wife and unborn child to the void. Legend of an ancient sword said to prevent the wielder from becoming corrupted by the void, lost in Icathia, brought him to research ancient texts (like Kassadin did), and search for it south of the Great Barrier. After years of research and failed attempts he finally discovers Icathia and the sword, which lie in an unknown ancient soldier's grave. Upon entering the void, he discovered that the sword did not make him immune to the void's corruption, just prevented it from taking over completely. He since appears to only be half-human.

All names are undecided

------------------------------------------------------------------------- ABILITIES -----------------------------------------------------------------------------------

PASSIVE: basic attacks alternate between swords. Left sword deals magic damage (base AD + 70% AP applies on hit and can critically strike as normal). Right sword deals physical damage (100% AD scaling). When out of combat, next basic attack defaults to right sword, or "main sword" if is W learned. Abilities using right sword can critically strike and apply on-hit effects instead of spell effects.

Q: 9/8/7/6/5 cooldown; 55/60/65/70/75 mana Your next basic attack cleaves enemies in front of you with both swords for 40/45/50/55/60% of both swords' damage. Applies 30/35/40/45/50% slow that decays to 0 over 1.5 seconds.

W: Passive: each sword applies its own stacking effect for 4 seconds, at 6 stacks the stacks are consumed to deal 4/6/8/10/12% +2% per 100AP hp magic damage (left sword), or 30/60/90/120/150 + 100% bonus AD physical damage (right sword) over 4 seconds, and you gain 20/25/30/35/40% attack speed for 4 seconds. Each sword's passive cannot proc on the same target more than once every 8 seconds.

•   Toggle: choose main sword (which sword your E and R use).  (1 second cooldown)
  

E: 13/12/11/10/9 cooldown; 30/40/50/60/70 mana After a brief delay dash quickly in a direction through all units striking all enemies champions for 60/70/80/90/100% main sword damage. Cooldown reduced by 2 seconds per enemy champion hit. (500 unit dash)

R: 90/75/60 cooldown; 100 mana Throw main sword in a line for 50/100/150 +100% main sword damage, applying 1/2/3 stacks of main sword's W passive, sticks to first enemy champion hit. Disappear into the void for 0.5 seconds then appear under your sword, knocking enemies up for .75 sec.

I would expect that all this takes a few minutes to understand, but basically your left sword does magic damage and was corrupted by the void, your right sword does physical damage and was taken off of the ancient soldier's grave, and each has its own stacking debuff that applies damage over time once applied 6 times. The benefit of using the right sword is on-hit effects and crits, the benefit of using the left sword is spell effects and for shredding a tank with 6 stack %hp damage + . Being able to proc both would require a very long fight, but procing one wouldn't be too difficult. I imagine the E dash being similar to Falco's or Fox's dash in Super Smash Bros.

Let me know what you think in comments.