Champion Idea: Mimick
Just a fun idea I think. Stats are for a standard mage, or maybe a support, not sure which would be better.
Passive-
Fast Learner: Gain bonus experience equal to X% of amount earned from nearby unit deaths. Or gain bonus experience equal to X amount per second.
Q-
Magic Mirror: Redirect incoming projectiles in the opposite direction, these will damage ALL units, friend and foe. The size would be relatable to Yasuo's wind wall although probably a tad smaller.
W-
Enter the Box: Trap an enemy champion in a magic box (snares for 1.25 seconds) enter your own box and trade places with the enemy champion.
E-
Lifeline: Throw a rope around an enemy or friendly champion, and pull them toward you.
R- Ultimate ability
Copycat: Copies the last ultimate used within a 1500 unit radius. Global ultimates (TF, Nocturne, Raka, Karthus) are considered 0 units from you. For champions. May "lock in" your ultimate selection for 20 seconds.
I'm not sure how it would react with Udyr/Elise/Jayce and similar champs, but I think it would be really cool. Also I'm not entirely sold on the E or the W just yet...I'm open to suggestions.