Heal for a percentage of damage dealt with your abilities. Increases with each unique takedown.
Offense
+5 AD or 9 AP
Flex
+5 AD or 9 AP
Defense
+6 Armor or 8 MR (match-up)
WhySummon Aery
Aery is taken here for it's reliability and chip damage when trading with [Q].
Pay attention to it's return to you and look to proc it as often as possible with [E] poke.
WhyManaflow Band
Manaflow Band paired with your Hexcore upgrade is your primary means of mana sustain throughout the game.
WhyCelerity
In the mid to late game, Viktor has a nearly constant haste thanks to his empowered [Q]. The bonus Movement Speed from [Q] will grant you a bit of an AP steroid.
WhyScorch
Combined with Aery, Scorch is a great rune for taking small trades and chipping away at the enemy in lane.
If you're looking for bigger damage in late game teamfights, Gathering Storm is a decent replacement.
WhyTaste of Blood
Taste of Blood offers you a fantastic trading pattern and extended laning so that you can remain in lane until you reach your first Hex Core upgrade.
WhyRavenous Hunter
Ravenous Hunter empowers your ability to completely take over late game teamfights where your massive extended damage output results in big healing and sustain.