Lane harassment and early duel power.
Burst damage and target access
Hitting a champion with 3 separate attacks or abilities in 2s deals bonus adaptive damage.
Gain a burst of Lethality and Magic Penetration after using a dash, leap, blink, teleport, or on leaving stealth.
Collect eyeballs for champion and ward takedowns. Gain permanent AD or AP, Adaptive for each eyeball plus bonus upon collection completion.
Heal for a percentage of damage dealt with your abilities. Increases with each unique takedown.
Creative tools and rule bending
Get a free biscuit every 3 minutes, until 12 minutes. Biscuits heal and permanently increase your max mana.
+5% Max CDR
+5% Summoner Spell CDR
+5% Item CDR
+6 AD or 10 AP
+5 Armor or 6 MR (match-up)
LeBlanc's assassination playstyle synergizes perfect with the burst damage play-pattern of Electrocute, allows you to easily proc it with a [Q]->[R].
LeBlanc makes great use of Sudden Impact, gaining bonus Magic Pen and Lethality when entering a trade/fight with [W].
LeBlanc is all about kills and snowballing. Eyeball Collection is a rune that further pushes your gains for every kill/assist.
LeBlanc's incredibly high base damage means that your self-sustaining harassment will be incredibly high paired with Ravenous Hunter.
Biscuit Delivery allows you to trades aggressively and often in lane thanks to your potion advantage when paired with Time Warp Tonic.
Cosmic Insight's general utility means more ability casts and damage output in teamfights.