An Assasin kit idea
Passive : Killer Instincts Attacking or damaging a enemy will mark them, causing some of your abilities have increased effects. Only one champion may be marked for this purpose. When a marked enemy champion is lower than 30% of health, X's gains permanent vision of them until they get higher than 50% health. At level 11, X's gains permanent vision of them when they get lower than 40% of health until they get higher than 60%.
**Q : Slashing Wave ** Range : 1000 CD: 8s X's cuts the air, landing a linear vertical wave that deals (50/80/110/140/170 + 70% total AD ). This pass through minions but will stop when it hits a enemy champion If it hits a enemy and they are within 300/350/400/450/500, X's dashes to melee range and slashes twice, applying onhit effects on both hits and dealing ( 25/40/55/70/85 + 35% total AD ) per hit. Both hits can crit. If the enemy is marked by killer instincts, both hits will crit.
W : Hide and Seek CD: 15s Hide: X's immediately goes invisible for 2 secs, regardless of taking damage. He can't move while invisible except if he uses Seek. Seek: X's marks a enemy champion, gaining (30%/40%/50%/60%/70%) movement speed if he moves towards them while invisible. If the enemy is marked by killer instincts, X gains another 2 secs of invisibility after using Seek.
E: Counter CD: 15/13/11/9/7s Dash range : 800 X's enters in a defensive position for 0.75s. If attacked, he denies the damage entirely and dashes behind the attacker, dealing (50%/60%/70%/80%/90% ) of the damage he would take before resistances plus 100% of his bonus AD. If the attacker is marked by killer instincts, the champion is stunned by 1s.
R: Parallel Universe CD: 120/100/80s Range : 1000 X's marks a enemy champion, while entering in a parallel universe. For 4/5/6 seconds, X's is only visible to the marked champion and deals 20%/25%/30% increased damage to him. He can still be damaged or CC'ed by skillshots or AoE abilities, but he takes 50% less damage and gains 50% tenacity from everyone except his target. If a champion is marked by killer instincts, X's takes 30% less damage from his target too.