A Mobile champion which can be played affectively in middle lane. She can deal a lot of damage with her couger late game and her Q spear. Her early game basic attack damage is quite high compared to other ap champions in mid so, you will win trades

flat ad marks, armour seal, m.r glyph and flat ap quint.
by this rune build, you will have a strong early game laning with high base attack damage with flat ad mark and high spear damage with flat ap quints.

-start with boots and 3 potions
-catalyst and ward
-rod of ages and glacial shroud
-deathcap
-lichbane
-Guardian angel

basically, you will have;
boots, rod of ages, glacial(frozen heart), deathcap, lichbane and guardian angel

you can get other items though and i recommend they are cooldown reduction items like zekes herald and shurelyas.

-in lane keep harassing with your basic attack and make lots of damage trades
-dont hesitate to use heal for extra attack speed
-put traps in jungle openings to avoid pesky counter junglers and gankers
-poke them with Q and buff your ad carry with heal before going cougar and rip the enemy team apart