Erikka, the Rune Thief.
Nothing concrete... not familiar with the entire lore, so I wouldn't want to try anything too ambitious. Maybe some other time.
But, basically? She's Ezreal's arch-nemesis, from way back while he was just an apprentice. They had a few run-ins during their numerous expeditions, usually fighting over one artifact or another, or it's intended... destination. She is drawn to magic, in all of it's forms (liiiike runes).
Her reasons for joining the League are largery a mystery (!!!). Seeing as how she's a world renowned thief, she's allowed to participate in hopes of the authorities keeping tabs on her.
She's not exactly evil, but she no saint either IF YO NO WHATIMMASAYIN. Basically, a Chaotic Neutral chick.
Difficulty: Very Muchly
Her autoattack is ranged.
Her resource is mana.
Erikka "steals" a certain amount of gold (10%-15%) from every kill made by a nearby enemy champion. (both creep and champion kills count) The area of effect is roughly as big as Erikka's sight radius
Q: Cover Fire [channel]
[Active] Erikka covers an area in a hail of arrows, granting all friendly champions in the area of effect a shield and bonus movement speed, while slowing and damaging enemies. Removes stealth while channeling.
Channels for 3-4 seconds. Moderate cooldown. Moderate-High mana cost. Medium range. Medium AOE. Shield and damage scale with AP. Shield remains after leaving the area for a few seconds.
Ranks will increase the strength of the shield, increase slow effect and damage, increase mana cost and reduce cooldown.
W: Tools of the Trade
[Active] Erikka throws a Hextech bomb at a target area, revealing the area, damaging enemies and applying a mark on them. Allied champions can attack the enemy to consume the mark and lower all of their current cooldowns.
High mana cost, moderate-long cooldown, long range. Damage scales with AP.
Ranks reduce cooldown, mana cost and increase cooldown reduction from marks.
E: Break Away
[Active]: Erikka removes all crowd-control effects on a friendly champion, grants zero unit collison and bonus movement speed to him/her/it and herself for a short duration.
[Passive]: Erikka gains tenacity.
Long cooldown, melee range, moderate mana cost.
Ranks reduce cooldown, increase movement speed buff on active, and improves her passive (max 10-15 tenacity).
R: The Grand Heist
[Passive] Permanent stealth (like the upcoming stealth re-work)
[Active 1] Erikka dashes forward (long skillshot dash). If she intercepts an enemy champion, she steals all of his/hers/its buffs, storing them for future use. This is a single-target skillshot.
High mana cost, long cooldown, medium-long range.
Once she intercepts an enemy champion, temporary buffs (red buff, baron, blood boil etc.) are removed from that champion completely, while 'permanent' buffs (auras, passive buffs, passive buffs from items etc.) are disabled for 2-5 seconds. Erikka still stores 'permament' buffs.
Ranks reduce cooldown and increase mana cost.
Erikka will have these buffs stored indefinitely, only losing them upon death. She does not enjoy the benefits of the buffs themselves, until she activates...
Only available if Erikka has stored buffs.
Gives Erikka the ability to grant any ally (or herself) all the buffs she had stored. Stored temporary buffs (red buff, baron, blood boil etc.) are refreshed to their maximum duration, while stored 'permament' buffs (auras, passive buffs, passive buffs from items etc.) last for 5-7 seconds after activation. Cooldown for The Grand Heist starts after you activate Payday.
While Erikka has buffs stored, golden runes will orbit her, and her stealth will be disabled. If an enemy champion manages to kill her, he/she will receive all the buffs Erikka stored (similar to Payday on opposite day) and bonus gold.
Alternate idea for her passive: Counterfeit Casket
Erikka starts with a magical casket in her inventory, which cannot be sold. The casket will periodically spawn random consumables within it, based on Erikka's level. She can use the casket to activate whatever item is currently in it. Potions can also be used on allied champions, and are automatically consumed.
Alternate idea for E: Sap Arcana
[Active] Erikka removes all debuffs on target allied champion, and will give that champion one stack of Sap Arcana for every debuff she removes. Each stack gives bonus health regen.
-Removed gold per ten seconds bonus for Entrepreneur.
-Removed passive speed buff on Break Away.
-Stealth will be inactive while you're carrying stored buffs, and the enemy will gain bonus gold for the kill.
-Adjusted mana costs and stuff.
-Added altrenate idea for E and her Passive.
All comments and criticism art welcome.