1. Introduction 2. Why play Viktor? 3. Pros/Cons 4. Summoner Spells 5. Runes 6. First Strike or Summon Aery on Viktor? 7. Abilities 8. Skill Sequence

9. Items 10. Mythic Items 11. Early Game 12. Mid Game 13. Late Game 14. Tips and Tricks 15. How to farm and freeze 16. Warding 17. Roaming

18. Playing from behind 19. Matchups 20. Synergies 21. What to ban? 22. Which champions you should avoid picking into Viktor? 23. How to counter Viktor? 24. Conclusion

Hello everyone and welcome to "My Viktor's Build" guide. I am EUNE League of Legends player and my name in game is Hektor Ulmer (not my real life name, it's just what I added). My rank in other account was Diamond III, but I can't really remember my old account name because I took a break from the game for a several years but I really don't mind that and now I created new account to play for fun and not to be the best player in the game. My favourite champion in game is Viktor. I play many roles but my best role is Mid and Top lane. From that being said, I am going to show you why Viktor is the best mage champion to play. If you don't wanna read my guide and if you are only interested on items, that is fine for me because I created this guide for any players who mains Viktor to get better in ranked or to play him just for fun. :)

Abilities

Viktor - The Machine Herald Ranged Mage Champion Damage Type: Magic Mid Lane: Strong Difficulty to play: Hard Viktor is perhaps one of the best scaling mages in the game with crazy AOE damage, strong waveclear, great zone control and good mobility thanks to his Siphon Power from his passive Glorious Evolution once upgraded and he has one of the best ultimates Chaos Storm in teamfights. He also does great against almost any mid laners once you have purchase few items and upgraded first ability from passive Glorious Evolution and there is no way that enemy champion can do to you if you of course, didn't die early and if you are well farmed. From my experience, let me show you everything you need to know and how to play Viktor.

Pros +Strong waveclear once you upgraded your Death Ray +Crazy AOE damage with his Chaos Storm +Great zone control +Great at kiting +His ultimate Chaos Storm can interrupt channel abilities +Does absolute amazing job in teamfights +Very hard to destroy Viktor once he is fed +Becomes GOD in late game once he has full items +He has probably best dance in League Viktor has an insane late game scaling thanks to his passive, excellent waveclearing, burst damage, crowd control and it will be almost impossible to 1 vs 1 Viktor with full items and good mobility from his upgraded Siphon Power. He can almost 1 shot squishies from his Siphon Power, kite with Death Ray and can stop chanelling abilities with his Chaos Storm making him one of the bast teamfighting champions in the game. :)

Cons -Like all other mages, he is squishy -Weak early game -Bad waveclear before upgrade -Hard to play -Immobile, which he can be easily ganked -Weak when behind -Needs time to scale -Weak against assassins and gap closers -Players often ban him in draft modes :/ Unfortunately, Viktor has many weaknesses. He is squishy like other mages, weak in laning phases, can be easily ganked since Viktor is pretty immobile champion and has a low range abilities besides from his Death Ray. It is also quite hard to play with him. He also has some bad matchups against few assassins, gap closers and long range champions. :(

FLASHFlash is the most important spell in the game. It helps you from escaping nasty situations and also for chasing and killing enemies whenever you can't reach them. Always take this every game!

TELEPORTTeleport is very good summoner spell on Viktor. It can be used to teleport on allied towers and it has a 360 seconds of cooldown. After 10 minutes, you can cast on allied minions, wards, towers and other allied constructs and has a 240 seconds of cooldown. This is where I take 90% of the games as a Viktor player.

IGNITEThis is a summoner spell where you wanna play aggressive for having kill pressure against champions who has a weak early game or against a champions that heals a lot such as Sylas, Vladimir etc. It helps you to get an early kill and with your passive Glorious Evolution, you will upgrade your abilites much faster. I rarely take this if their enemy team has a lot of healings or if I wanna have killing pressure to win my lane.

BARRIERThis is a MUST spell against burst champions such as LeBlanc. It helps you to survive early and it has a pretty low cooldown and it is good against champions who has Ignite.

EXHAUSTThis spell helps a lot against champions that has burst damage or reliesing on autoattacking a lot such as Yasuo, Yone etc. Having Exhaust makes great 1 vs 1 dueling but take this spell only if your ADC or Support doesn't have.

CLEANSEIf the enemy team has a lot of CC, then Cleanse is a must have. I usually take against heavy CC mid such as Annie, Lissandra or Zoe. It also removes Ignite damage but not healing reduction so keep in that mind.

GHOSTSince Viktor lacks of mobility, this spell also benefits on him and scales greatly in late game. I don't take this as a main Viktor but if you feel you need more mobility, then Ghost is good to go.

Keystone First Strike is an absolutely amazing keystone on Viktor from now on. It gives you 5 gold and for 3 seconds, you cause all of your damage dealt against champions to deal 9% bonus damage. After 3 seconds, you gain a gold based how much you dealt damage. This is suprisingly ridiculous good rune for Viktor (even after a bit nerf, it doesn't really matter, it's still good). You can purchase items even faster and this rune scales much better in late game than any other runes. Tier 1 Magical Footwear gives you free boots at 12:00 and for every takedown, it reduces cooldown by 45 seconds. This is great where you don't have to spend 300 gold in shop but keep in mind that you cannot buy boots before then. Tier 2 Biscuit Delivery gives you every 2 minutes until 6 minutes (max 3). It restores health and mana and the lower you are, it restore much faster. Consuming or selling gives permamently increase your mana cap by 40 which is really nice for mages such as Viktor since he lacks of sustain. Tier 3 Cosmic Insight gives you cooldown reduction from your Summoner Spells and Items which is really good as you can activate earlier than usual. Tier 1 Manaflow Band is great for any mages. When fully stacked, you gain permamently 250 bonus mana and passive that restores 1% of missing mana every 5 seconds. This is important for Viktor since he can be mana hungry early. Tier 2 Transcendence gives you cooldown reduction upon reaching levels. Having lower cooldowns means you can spam more abilities very often. diamond For offense take attack speed. It will help you to last hit minions faster and also trade better against your opponent with auto attacks. For flex take [diamond Adaptive. It gives you more AP early. For defense, take magic resist against easier AP matchups. diamond Same goes from above but with armor against AD matchups. diamond This is where you wanna take double magic resist against hard AP matchups such as LeBlanc. diamond This is where you wanna take double armor against hard AD matchups especially against assassins where they can burst you down quickly such as Zed. diamond If you are not sure who is going to be your opponent in mid lane for example if their enemy team has Ekko and Irelia and one of them can be mid, then take for defense health. This is my 2nd viable First Strike but with sustain: Tier 2 Time Warp Tonic gives you much more sustain with your Corrupting Potion and biscuits and also grants you 5% movement speed while under effect. And this is that I use against easy/fre matchups that they don't have any kill pressure on you and you can freely scale: Future's Market is good if you wanna buy items earlier escpecially if you are thinking that you will struggle a lot against some nasty matchups. Tier 3 Gathering Storm is very good on scaling mages such as Viktor. It's pretty weak early but later it will become much stronger and you will be able to deal much more damage. If you don't wanna use these runes, there are other options you can use as Viktor. I am going to show you some other viable runes: This is my Summon Aery Rune page Sorcery: Keystone Summon Aery is very strong for early game to trade well against your opponent. When you damage an enemy champion with auto attack or abilities, you send a little buddy to deal them a damage. Tier 3 Scorch is good to bully enemy champions early. It sets them fire to deal damage after 1 second. This is my Arcane Comet Rune page for those who want to deal are damage (it's good against long range champions): Keystone Arcane Comet is also viable choice for Viktor especially if you are facing against long range champions that will poke you from distance. This Rune scales better than Summon Aery in late game and it's quite hard for the enemy to dodge it if they don't have enough movement speed. This is Phase Rush Sorcery Rune page for those who wants more movements speed and kite your enemy champion: Keystone Phase Rush is very good on Viktor. Since he lacks of the mobility, this rune will help him a lot to chase or escape from the enemies. It is also very effective in teamfights as well. And this is my viable Domination: Keystone Electrocute gives you bonus adaptive damage when you hit an enemy champion with 3 seperate attacks or abilities. With this rune, it will make you like an assassin mage. Tier 1 Taste of Blood heals you when you damage and enemy champion. Tier 2 Eyeball Collection: Each enemy champion takedowns, you collect eyeballs for AD or AP. Tier 3 Ultimate Hunter gives you cooldown reduction of your ultimate for each enemy champion takedown. If you are against hard matchups, I suggest to take this rune page. If you are against hard AD champion, then put double points on armor, if against hard AP champions, then put double points on magic resist (you may choose First Strike for scaling or Summon Aery for early trades but use Shield Bash, Bone Plating and Time Warp Tonic for sustain so you can have an easier time): Tier 2 Perfect Timing is good when you don't wanna waste 650 gold in shop and each takedown reduces your timer. This is viable against matchups such as Fizz, Zed etc. to avoid their ult. Tier 1 Shield Bash is very good on Viktor due to your shield from Siphon Power. When you gain a shield, you will gain a small Armor and Magic Resist and your next basic attack will deal bonus damage to an enemy champion. Tier 2 Bone Plating is good to receive less damage from spells or attack from the enemy champions. This can be very helpful against hard matchups especially against assassins and burs champions. Other Viable Runes: For Inspiration: Unsealed Spellbook is underratted and yet rarely taken on many AP champions and other non AP champions as well. You can swap your summoner spell which you want to use it and it decreases your cooldown the more you choose different summoner spell. Minion Dematerializer is good if you want to insta delete any minions. I recommended to use on cannon minion to gain 5 Hex Fragments so you can scale much faster. For Sorcery: Nimbus Cloak gives you bonus movement speed when you cast a Summoner Spell. The higher cooldown of Summoner Spell is, the more movement speed you gain. Absolute Focus is good for the early game whe you wanna bully your enemy champion. This works only when you have more than 70% HP. Celerity increases your bonus movement speed effectivenes. This works well with your upgraded Siphon Power or if you took Summoner Spell Ghost. Waterwalking gives you bonus movement speed and bonus Adaptive damage while on river. It's very good for those who want to roam a lot and it helps you to deal more damage for example: if you are near at dragon or baron. For Resolve: Overgrowth helps you to increase your health permamently. Each essence from monsters or minions that die near you, you will gain small amount of health permamently. You also gain an additional maximum health when you absorbed at least 120 monsters or minions. Unflinching gives you tenacity and slow resistence. The lower your health is, the more tenacity and slow resistence is increased. This is good if the enemy team has too much CC. For Domination: Dark Harvest can be situational as a Keystone of you want to deal more damage to the enemies below 50% health and scale much better in late game. Treasure Hunter gives you gold for each takedown on enemy champions. This is good for those who wants to be rich and get Items faster. Relentless Hunter gives you permament out of combat Movement Speed for each takedown on enemy champions. This is good since Viktor is immobile and you can get in teamfights or other objectives faster. For Precision: Presence of Mind gives you mana regeneration when you damage an enemy champion. When on takedown, it restores your mana. This rune can help if you spam a lot of your abilites and go aggressive. Coup de Grace is really good for those who wants to deal more damage. The more damage you will deal when the enemy champion has lower than 40% HP. Last Stand is good when you want to deal more damage to an enemy champions when you hae lower health.

FIRST STRIKE

VS

SUMMON AERY

So people are started to thinking which rune is best in Season 12 on Viktor. First Strike or Summon Aery? Some people think that Summon Aery is best right now due to the strong early game poke but some are thinking that First Strike is better because it's very good in the late game and gives you a gold based how much you have dealt damage on the enemy champions or some people are using Phase Rush or even Electrocute. So let's see what these 2 Rune Keystones that are very strong on Viktor do:

FIRST STRIKE

PASSIVE: Dealing damage or applying a crowd control effect to an enemy champion within the first 0.25 seconds of champion combat, grants 5 Gold 5 and First Strike for 3 seconds, causing all of your post-mitigation damage dealt against champions to deal 10% bonus true damage. Afterwards, you are granted (Melee 100% / Ranged 70%) of all bonus damage dealt within the duration as gold. First Strike will be placed on full cooldown after being struck by an enemy champion before you strike them. Cooldown: 25 - 15 (based on level) seconds

SUMMON AERY

PASSIVE: Damaging basic attacks, abilities, item effects, and summoner spells against an enemy champion signal Aery to pounce at them over 0.45 seconds, dealing 10 − 40 (based on level) (+ 15% bonus AD) (+ 10% AP) Adaptive damage. Healing, shielding, or buffing an allied champion signals Aery to jump to them over 0.35 seconds, shielding them for 35 − 80 (based on level) (+ 40% bonus AD) (+ 25% AP) for 2 seconds. Aery applies her effects upon arrival. Aery then lingers on the target for a little less than 2 seconds before flying back to the user, and cannot be sent out again until she returns. Aery is initially very slow, but gradually accelerates, and can be picked up by moving near her.

As you can see, these Rune Keystones do different damage. First Strike gives you 5 gold and begins to deal extra damage for 3 seconds after dealing damage or applying crowd control on the enemy champion. Once the 3 seconds have passed, you will receive a gold based how much you have dealt. Note that First Strike deals TRUE damage which is cool. It has a 15 seconds cooldown when you reach maximum lvl 18. This rune is pretty weak early but it gets stronger in mid and late game.

Summon Aery is a poke rune that deals bonus magic damage on the enemy champions when using basic attack, abilities, item effects or summoner spells as well. You can see her when she lingers the target and it will fly back to you. It's pretty slow but it moves faster and you can pick her back by moving near her. This rune is way stronger early than First Strike but it doesn't do much in the late game as you would expected. You can pretty much win trades against enemy champions early rather than First Strike. Unlike First Strike, it doesn't give any gold.

But what does First Strike makes so great for Viktor:

1. His Q Siphon Power can be used as an early tool for poking your enemy. Not necessarily for killing them but for farming extra gold.

2. Viktor will deal the most damage with his E Death Ray which is his main harass ability and this ability will give him the most gold.

3. If the opponents get way too close for comfort be sure to lock them in place with your W Gravity Field and unleash your abilities and watch how much you will gain gold while dealing damage.

4. All of his basic abilities can be upgraded or augmented each time he gets a kill and once you have all upgraded abilities, you will gain even much gold than before.

5. He is a scaling mage champion meaning First Strike is extremely good on scaling mages for late game or even some assassins.

Both of these Rune Keystones are very good on Viktor. You can choose First Strike for poking (not necessarily for killing them but for farming extra gold) and scaling into late game or Summon Aery for stronger early game poke and winning most of the trades especially if you have Ignite. What I choose? I choose First Strike for scaling and farming for gold because it's really cool and great Rune for Viktor and I think it's way better than Summon Aery. With my upgraded abilities and full build, I will one-shot almost everyone in the late game (not against tanks). From my experience, First Strike is a must try on Viktor until it gets nerfed and believe me, you won't be dissapointed. :)

Glorious Evolution (Passive) RANGE: N/A COST: N/A COOLDOWN: N/A

INNATE: Viktor can augment his basic abilities after gaining 100 Hex Fragments, he obtains them by killing enemy units: Minions and monsters grant 1 Hex Fragment. Large minions grant 5 Hex Fragments. Champion takedowns grant 25 Hex Fragments. Chaos Storm Chaos Storm gets augmented once of all his basic abilities have been augmented.

Siphon Power (Q) RANGE: 600 COST: 45/50/55/60/65 COOLDOWN: 9/8/7/6/5

Viktor blasts an enemy unit, dealing 60 / 75 / 90 / 105 / 120 (+40% of ability power) magic damage while shielding himself for 27 − 105 (based on level) (+18% of ability power) for 2.5 seconds. Viktor's next basic attack is converted into magic damage, dealing 20 / 45 / 70 / 95 / 120 (+ 100% AD)(+60% of ability power) magic damage. AUGMENT- TURBOCHARGE: Viktor gains 30% bonus movement speed for 2.5 seconds after using Siphon Power. Also increases Siphon Power's shield value by 60%, up to 48 − 184 (based on level) (+ 32% AP).

Gravity Field (W) RANGE: 800 COST: 65 COOLDOWN: 17/16/15/14/13

Viktor conjures a gravitational imprisonment device at a target location for 4 seconds, slowing all enemies that pass above it by 28 / 32 / 36 / 40 / 44%. Whilst under its effects, enemies generate stacks every 0.5 seconds; at 3 stacks the target will be stunned for 1.5 seconds. AUGMENT- MAGNETIZE: Viktor's abilities, excluding Chaos Storm, slow enemies hit by 20% for 1 second.

Death Ray (E) RANGE: 525 COST: 70/80/90/100/110 COOLDOWN: 12/11/10/9/8

Viktor uses his robotic arm to fire a 500-unit length laser beam across the field in a chosen path, dealing 70 / 110 / 150 / 190 / 230 (+50% of ability power) magic damage to every enemy it hits. Augment - Aftershock: An explosion follows Death Ray's wake, dealing an additional 20 / 50 / 80 / 100 / 140 (+80% of ability power) magic damage.

Chaos Storm (R) RANGE: 700 COST: 100 COOLDOWN: 120/100/80

After a 0.25 second delay, Viktor conjures a singularity at the target location, dealing 100 / 175 / 250 (+50% of ability power) magic damage and interrupting channeled abilities. The storm cloud remains for 6 seconds afterwards, firing lightning bolts which deal 65 / 105 / 145 (+45% of ability power) magic damage to all nearby enemies every second. While the singularity is active Viktor can re-activate Chaos Storm to move it to the cursor's location or at an enemy champion. The singularity moves faster the closer it is to Viktor. AUGMENT- PERFECT STORM: The Chaos Storm moves 25% faster.

You should start at lvl 1 with ability Siphon Power because you will begin to harras enemy champion in laning phase. With this ability, there is no other champions that can deal with you since you deal a nice amount of damage and you gain small shield that absorbs some damage. Then at lvl 2, you put a point into Death Ray since this is the main ability and you will be maximize this ability as soon as possible and then at lvl 3 Gravity Field. Death Ray is the main source of damage and poke, while Siphon Power is the second ability to max after Death Ray and finally the Gravity Field at last. Always put point at lvl 6, 11 and 16 Chaos Storm.


You can also put point at lvl 1 Death Ray if you are against ranged champions and you can clear first 3 minions easily or if the enemy team is going to invade so you can poke them and use in bushes if they are hiding.


In some matchups, you wanna put a point at lvl 2 Gravity Field if they have a gap closers let's say you are up against Tristana mid and she will use her Rocket Jump at lvl 2 to jump on you to deal damage and auto attack you and you can use your Gravity Field on her so you can escape. This will save your life to run away and preventing them for getting kill.

Starting Items:

DORAN'S RING A standard item for most of the mages. It gives you Aility Power, Health and a passive that restores mana when you damage and enemy champion. This is where I start in almost every single game and every player should start too.

CORRUPTING POTION Another option to start that gives a lot of sustain. Since Viktor doesn't have any sustain abilities, it is good to trade early game against any enemy champions especialy against melee. If you combine together with Biscuit Delivery and Time Warp Tonic, it will give you tons of sustain so you will be able to stay in your lane for much longer which is awesome.

DARK SEAL If you wanna to snowball or thinking that you have an easy opponent, you can go for this item since it gives you more Ability Power for each takedown and you can later upgrade to Mejai's Soulstealer. Obviously, you should start this only if you think you can really snowball hard or you can buy this Item when first recall.

SAPPHIRE CRYSTAL If you are planning to rush early Lost Chapter and don't wanna waste your gold like Doran's Ring, then this is good start. Since Viktor has a bit mana problem early, this item will help you to spam your abilities a bit more.

TEAR OF THE GODDESS If you are having with mana trouble early especially if you are facing against manaless champion, you can start with this item. It will help you to increase your mana and you can stay in your lane for much longer and spam a lot but please do not upgrade into Archangel's Staff because, it's not good anymore on Viktor as it only gives ability haste, not ability power anymore. Once you are almost full build, sell your Tear of the Goddess and buy something stronger.

STEALTH WARD You must ALWAYS start with Stealth Ward. It reveals surrounding area so you can see on the map if the enemy junglers comes to gank you or if enemy mid laners goes roaming. Later after the enemy or your tower in mid lane is destroyed you can keep it or you can buy Farsight Alteration or Oracle Lens depending what the enemy team comp looks like.

First Recall:

LOST CHAPTER You must get this item as soon as possible. This is very important item for every mages to upgrade into mythic item of their choices.

SEEKER'S ARMGUARD If you are facing against AD assassins especially against harder matchups, then get it to survive their burst. Without that, you will be easily killed and they will start to snowball.

VERDANT BARRIER If you are facing against AP burst, then this item will help you to survive. Later upgrade it into Banshee's Veil.

CATALYST OF AEONS This item and Rod of Ages is back. It doesn't give you Ability Power but it gives you Health instead. Build this only if you are going for Rod of Ages. Don't build Lost Chapter together because Rod of Ages is also Mythic item and you won't be able to upgrade your Lost Chapter.

OBLIVION ORB If you are against some champions that heals a lot, then you can buy this as a first item. I don't buy this before Mythic item even if I struggle.

CONTROL WARD Buy this often when you are going to recall. It will help you to reveal location and invisible wards so you can clean them. This also reveals invisible champions such as Twitch. Put it in the bush near enemy red buff, players often don't see there.

Mythic Items:

LUDEN'S TEMPEST If you are playing against a squishy enemy team, then this item is a must buy. If you combine together with Sorcerer's Shoes, Lich Bane and Shadowflame, you will completely delete one enemy champion if he of course doesn't have any magic resist. This Mythic Item is currently best right now on Viktor or any other mages for now so you should buy it if the enemy team doesn't have any bruisers or tanks.

LIANDRY'S ANGUISH This item is good if the enemy team has a lot of bruisers or tanks. It's also effective against a champions that you are facing in laning phase such as Cho'Gath or Vladimir. This is by far the best scaling item on Viktor.

CROWN OF THE SHATTERED QUEEN If you are facing against a burst champion or any assassins especially if you struggle a lot, then this Mythic Item will help you. Unlike Luden's Tempest, it's quite cheap, it gives you some defensive stats and has a passive that can make you to become safeguarded and gain 75% damage reduction and while safeguarded, you gain some AP.

EVERFROST If the enemy team has a lot of gap closers and dashes, then this Mythic Item will defenitely help you. It's also effective against some matchups such as Irelia, Yasuo etc since they have almost infinite dashes. Since this Mythic Item has been nerfed (slow/root has been reduced from 1.5 to 1 seconds), I think it's still fine item to buy.

ROD OF AGES Rod of Ages is back for beloved players! This item is currently strong right now. It gives you Ability Power, Health and Mana and each minute it increases your Ability Power, Health and Mana up to 10 times. After reaching max stacks, you will gain a level and it will improve your other passive that restores your Mana and Health upon taking damage from champions. This item is very good for many mages and AP bruisers but the downsides it slowly scales in late game. I still do not prefer to build on Viktor as he needs more Ability Power and Haste to deal more damage from his spells. Still, it's a very good Mythic item if you want to be more tanky in late game.

Boots:

SORCERER'S SHOES My standard boots for almost every game. It gives you flat magic penetration which is good for early and mid game.

IONIAN BOOTS OF LUCIDITY Quite good for CDR. With these boots, you will be able to spam your abilities a lot. Also, reduces your cooldown on your Summoner Spells.

MERCURY'S TREADS If the enemy team has a lot of CC or that deals a lot of magic damage, then these boots are must to buy. I buy this when I am facing against Veigar to reduce his stun from his Event Horizon and against strong burst mage LeBlanc.

Core Items:

SHADOWFLAME This item is very powerful on Viktor. It ignores 10-20 of the target's magic resistance depending how much health they have. Very good especially if they have a bruiser or tank or if they have a lot of shields. Combining together with Sorcerer's Shoes and Void Staff, you will do an insane damage and you can deal enough damage even if they are tanks.

ZHONYA'S HOURGLASS Very good item especially if you are facing against AD champion especially if they are assassins. This item will save you a lot especially against some ultimates such as Fizz Chum the Waters or Zed's Death Mark. I buy this almost every single game to survive in teamfights and to counter some deadly ultimates. You should also buy it to survive any nasty situations.

RABADON'S DEATHCAP Probably the most important and ultimate scaling late game item that every mage buys. The passive gives you a massive increase of Ability Power. Buy it after Mythic Item only if you are very fed and have enough gold, if not, then buy it as a 4th or 5th item.

VOID STAFF Very good item for any mages. This Item will help you to ignore their Magic Resist as you will deal even more damage to bruisers or tanks. You can buy it earlier especially if you are against like Galio since he will build a lot of Magic Resist Items but you should buy this as a last item if the enemy team has Magic Resist Items.

LICH BANE This item is amazing on Viktor. The spellblade passive works together with Siphon Power and with his empowering basic attack, he will deal massive damage or can completely one shot squishy champion. Buy this as a last item if the enemy team doesn't have any Magic Resist Items.

Situational Items:

BANSHEE'S VEIL This item grants you a spell shield that blocks champions ability and it's very good against heavy AP team or against burst mages such as LeBlanc, Veigar etc. I buy this item when I am facing against Veigar to reduce his stun and survive his ridicilous burst in late game or if they have a lot of CC.

MORELLONOMICON This item is good if their enemy has a lot of healings or if you are facing against healing champions such as Sylas, Vladimir etc. This item now gives Magic Penetration after some changes which makes this item even more stronger against healing champions.

COSMIC DRIVE Gives you great Cooldown REduction, Ability Power and Movement Speed and a passive when you deal damage to enemy champions with basic attacks or abilities 3 times, you will gain bonus Movement Speed and AP. This Item no longer gives Health but it gives you much more AP than before and now it's really strong Item for Viktor especially if you have a Keystone Phase Rush.

DEMONIC EMBRACE A good item against bruisers and tanks as you gain Ability Power equal to your health and dealing damage to enemy champions causes of them as maximum health.

SERAPH'S EMBRACE This item has been changed and now it gives you Ability Power instead of Ability Haste based how much you have mana. It now has a new passive that gives you a shield when you are below 30% health. The more mana you have, the more shield you will gain. I think this item will be defenitely strong especially into tanky team and also against assassins that can save your lifes. I will try this item in the future games and let you know if this item is worth to buy on Viktor.

HORIZON FOCUS Honestly, I haven't tried yet that item, but I think it's only good for long range mages who spams abilities from long distance. Your only long range is Death Ray but if you wanna try this item, then maybe it will be worth it.

MEJAI'S SOULSTEALER An upgraded item from Dark Seal if you snowball really hard. Not reccommended to use in ranked games unless if you are very professional player.

Elixir:

ELIXIR OF SORCERY If your build is full, then always buy Elixir of Sorcery. It is the best elixir for any mages. It gives your AP, Mana Regeneration and it has a passive that deals True Damage to the enemy champions and turrets.