Umbrara - resurrected plague
http://s32.postimg.org/k6rvdhxwl/c4417db097ae2d24f531448fc8ba2eab.jpg
Melee champion: assassin.
Festering blades (passive): your basic attacks against enemies, who are showing you their backs, will cause them to suffer 20/25/30/35/40/45/50/55/60 (0.3 AP) magic damage over 8 sec. Stack up to 3 times. Any additional application will refresh this damage over time effect.
Shadow stalker (q): become invisible for 4 sec. Next basic attack, while you remain invisible, will inflict fear to all nearby enemies, except your basic attack target. Fear will last for 1/ 1.2/ 1.4/ 1.6/ 1.8 sec. Usable only when no enemy champion have vision on you. If you use this ability while enemy have a ward nearby and that ward is revealing you, instead of becoming invisible, you will reveal that ward for 5 sec. (range of fear: 320) (cooldown: 20 sec) (mana cost: 50/55/60/65/70)
Plague jumper (w): jump to an enemy target and infect it, causing your target to suffer 80/105/130/155/180 (0.65 AP) magic damage over 6 sec. If enemy already have a damage over time effect on him, then cooldown of this ability will be 50% shorter. (range: 500) (cooldown: 14 sec) (mana cost: 45/51/57/63/69)
Toxic assassination (e): become immobilize until you reactivate this ability. After short delay (1.25 sec) you can reactivate this ability to dash towards your cursor, stopping at fist enemy you encounter. That enemy will be poisoned and suffer 80/110/140/170/200 (0.4 AP) magic damage over 9 sec. If you hit enemy into his back, then that enemy will get two stacks of this poison applied to him. You can't dash through terrain. (range: 740) (cooldown: 18 sec) (mana cost: 80/84/88/92/96)
Lethal Toxins (R): your next 3 basic attacks within 5 sec will inflect you target, causing him to suffer 10/15/20% (1% for 50 AP) his max health as magic damage over 14 sec. This poison does not stack, but when you try to reapply it, then your will steal 90/120/150 (0.35 AP) health from your target and heal yourself for same amount. (cooldown: 90/80/70 sec) (mana cost: 100/90/80)
Poison meter: when you put enough damage over time effects on an enemy to kill him, then he will start glowing green.
Lore: a necromantic ritual was made and several wizards tried to bring back the strongest ancient wizard to life. These wizards were sure, that they will succeed. They collected remains of ancient wizard, but several other bones got mixed in with remains, so when ritual was performed, other being was resurrected instead of ancient wizard. This being killed his resurrectors, wrapped himself in their flesh and started roaming Valoran, assassinating wizards, mages and other people with strong magic powers. No one really knows who this creatures is, because he hides his face and always vanishes in the shadows without a trace.
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combined xD Lol