Viktor is a mage blaster/support, depending on how you play him.

Viktor is adept at rushing in to battle and dealing burst damage while taking little or no damage at all. Viktor has a decent amount of range and contains a slow/stun for CC, a lazer that can be aimed from a safe distance, and a unique ability - Power Transfer. Power Transfer does damage and returns a shield for a designated amount. This ability allows Viktor to harass without taking too much damage. Viktor comes out on top in mid lane, and he is able to adapt to almost any situation. With correct positioning, Viktor's spells can deal constant damage.

We grab Power Transfer first, allowing us to harass without taking too much damage due to the shield. Next is Death Ray, which allows the harass to deal quite a bit more damage. Another point in power transfer tops off the harass. Gravitational Field, Viktor's slow/stun, allows Viktor to easily harass because of an eventual stun. Power Transfer, followed by Viktor's ult, tops off our early game sequence.
Focus turns onto Power Transfer. After our fourth level in it, grab Death Ray again. When Power Transfer meets level five, Death Ray, followed by a point in our ultimate turns Viktor into a midgame machine, capable of causing full health to drop to around half without taking damage.
After Death Ray is maxed, our last skill, Gravitational Field, deserves some love. Two levels followed by a point in our ultimate leaves Gravititional Field the only remaining option.

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First, we grab a Doran's Ring. The overall +100 health and the nice mana regeneration bring this item up the ranks as a great first choice. The +15 AP also helps with harassing and with Viktor's shield. On the next recall back to base, grab sorcerer's shoes. If you have to recall before this, pick up boots and a few health pots. Next is a blasting wand. This applies some early game potential and aids our efforts to harass and dominate the lane. After, a quick Rabadon's and a giant's belt apply massive AP and some health to keep us alive. Shortly after, the giant's belt is built into Rylai's Crystal Scepter. The health and AP is outstanding; the passive is a great bonus. Void Staff helps Viktor apply the AP without having it become soaked up in Magic Resistance. After this, either an RoA (my choice) or a Zhonya's Hourglass add durability, as well as a hefty AP bonus. Upgrade your core to Augment - Death between the boots purchase and the blasting wand.

Standard runes. 3 flat armor yellows & 6 flat mana yellows allows for laning sustainability. Magic penetration reds and AP per level blues allow for mid-game dominance. The AP from the glyphs and Viktor's core's AP add up to substantial amounts.

These simple masteries pick up as much AP in offense as possible while grabbing Summoner's Insight and some movement speed in Utility.

Here, we'll go over multiple choices.
FLASH - An all-around amazing spell. Use it to flash into battle, reposition yourself, escape from a chase, juke, or dodge. Flash is a great choice no matter what.
TELEPORT - Allows for lane sustainability and quick trips to base. With the long cooldown, and the fact that Power Transfer allows for little to no damage taken while harassing, Teleport is not as good on Viktor as it might be on other champions. Teleport still is a viable choice. The feeling of teleporting to a ward behind your enemy and killing them is yet to be beat.
IGNITE - A great finisher for those enemies who you just can't land one more basic attack on. Great early-mid game, and adds up with Augment - Death's DoT.
GHOST - There is almost no need for this because of Gravitational Field, but if you feel inclined to pick up ghost, go for it.
HEAL - This adds a bit of sustainability in lane, but it isn't needed. If you find yourself being constantly harassed, pick up heal, but the long cooldown is hard to deal with.
SURGE - Viktor isn't a melee one-on-one fighter like Jax or Volibear. He doesn't need surge.
SMITE - WHAT ARE YOU THINKING!?!?!?!
CLARITY - Not needed too much, but if you're low on mana all the time, pick up clarity.
CLEANSE - Naw... If you get ganked, you're ganked. Flash out of it. Cleanse can't replace flash very well. In some situations, go for it, but you'd be better off with flash and a Quicksilver Sash if needed.

PROS b]CONS[/b]
Lane dominance Fairly vulnerable to ganks
Simple gameplay Countered by a champion with a jump (ex: Pantheon or Jax)
Loads of fun Needs decent positioning
Power Transfer New champion = only way to learn is to play over and over again
Not too squishy


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