This Dominion Karthus build assumes your knowledge of playing standard Karthus (mage, Summoner's Rift); you can read about it in my Karthus guide.
I won't describe here anything about standard Karthus playing; I will explain just the differences against this guide. I recommend you to read it.

Hello everybody.


First of all I want to say that english is not my native language, so please, forgive my mistakes :o(

When I start my playing in Dominion, I played Karthus by quite standard way (with some modifications for Dominion) - you can read my first Karthus Dominion guide about it.

That build worked well in some first days of Dominion game mode; I used to be the best player of almost every Dominion game by the score points with this build but I was feeding after few days when my enemies become skilled in Dominion (my points-score was still very good but I spent much time dead). This brings me to rework my build. With the new build I have about 60% win ratio, approximately 13/8/13 score and 1400 points per game (which makes me the best rated player in 90% of games) in Dominion.

I am -of course- curious for your opinions and potential discussion under this build; so vote and comment, please. But I ask you - before you downvote for whatever, read the original guide first (there is explained everything what is not here).

Before I start to guide you how to play Karthus, let me write something about Dominion. There are two teams trying to destroy enemy nexus to win - just like in the Summoner's Rift. But unlike in the Summoner's Rift, the nexus can't be destroyed directly.
There are five capture-points on the map. Each capture-point can be controlled by blue team, purple team or no team (it's grey then). If there is some team which control more capture-points than the other, that team is slowly destroying enemy nexus (the bigger is the difference between counts of capture-points by blue and purple team the faster is the nexus falling - e.g. if blue team controls four capture-points and purple team just one capture-point, purple nexus if falling faster than in the case of three capture-points controlled by the blue team and two capture-points controlled by the purple team).
How to capture the point? If some player right-clicks the neutral (grey) capture-point, he starts to capture it for his team by channeling (it takes several seconds). Other teammates can help him to capture it faster. The channeling (and capturing) can be interrupted by any damage from enemy champion (not minion). If the capture-point is not neutral (grey) but belongs enemy team, it's necessary to make it neutral (grey) first; this process is exactly the same as the process to capture neutral (grey) capture-point. It means that turn enemy capture-point to allied takes twice much time than capture neutral (grey) capture-point (e.g. if you want to make purple point blue, you have to change the purple to the grey and then the grey to the blue). Captured capture-point produce some creeps (that creeps attack enemies and/or slowly neutralize their capture-points by attacking). Captured capture-point works like allied turred as long as allied champion is around (e.g. blue capture-point behave like a blue turret as long as the blue player is below that - but if there is no blue player, blue capture-point doesn't attack purple enemy).
Other interesting aspects of Dominion:

• The game is so fast, almost no farming or staying somewhere, just fingting. The main advantage for me is that there is no time for flaming the chat and/or for finding out who failed in something.
• There are quests which apear during the time. The point of that quest is to capture some specific capture-point. Your quest is shown to both teams - one team sieges that capture-point, the other team defends it.
• There are some interesting places on the map: health packs (you can walk through and it restores you some health - but very low health), speed shrines (you can walk through to increase your speed for several seconds) and some crystal-prism things in the middle of the map (there are two crystals, one for each team; any member of that team can channel for few seconds to consume his crystal - that crystal improves you in many aspects and your character visually grows up; after your crystal is consumed, no other teammate can pick it for a while).
• Almost all time-intervals are decreased. There is much shorter respawn time (of players; there are no mobs). Recalling time is decreased to the half of the original time. The gold increases faster during the time. Experiences as well. All players starts on level three with 1375 gold. Whole the game lasts about 20 minutes and I think it can't be longer than 30 minutes unless it's not the intention of players.

Why to play Karthus as tank? To answer this question, we firstly need to answer another thing: Why to play Karthus as AP mage? Well, Karthus is one of the best heroes for teamfights: his damage output is multitarget (and awesome) and even if he dies, he stays in combat for seven more seconds. Due to Death Defied and Zhonya's Hourglass he has given fixed minimal time for dealing damage to many enemies (and even if he can't move as a Death Defied's ghost, he still have Requiem that can't be interrupted in a ghost-form). During this time you must deal as much damage to as much enemies as you can. That's simple. AP is clear choice.
Now imagine another situation. You aren't limited by any time, you just want to deal as much damage as you can untill you die; no great teamfights, just smaller fights or defending turrets which can take quite long time. Since Karthus is dps (not burst), we can make some easy simulations.
Standard Karthus AP build gives him about 2500 HP, 100 amor and 50 magic resist (there are many posibilities, this is something average). It means he can absorb 5000 physical damage OR 3750 magical damage before he dies. This tank Karthus has 3285 HP, 341 armor and 144 magic resist which makes him able to absorb 14487 physical damage OR 8015 magical damage before he dies (or 17795 PD OR 9845 MD with Guardian Angel's passive ready). So " Karthus the Tank" is in average 3x resilient than " Karthus the Mage" so he can stay about 3x more time in fight. What about damage? " Karthus the Tank" has no AP so he deals just 120 damage by Lay Waste and 110 damage by Defile per second (assuming one Lay Waste per second). " Karthus the Mage" has about 600AP (in average) so his Lay Waste deals 300 damage and his Defile deals 260 damage per second. So " Karthus the Mage" deals 2.4x more damage than " Karthus the Tank" but he can endure it for 3x shorter time; it means that " Karthus the Tank" deals about 25% more damage in total.
This is -of course- just simplified model; it doesn't include many factors (positive or negative for both builds) which can't be calculated in any math model. I will summarize them in the next chapter.

Advantages and disadvantages for standard Summoner's Rift Karthus you can find here. The same for Dominion Karthus you can read here.
In this build I just compare " Karthus the Tank" with " Karthus the Mage" for Dominion. I think that " Karthus the Tank" is better for Dominion (and my experiments with that confirm it).

Advantages of " Karthus the Tank" over " Karthus the Mage":

• 25% more damage in long fight
• can beat more champions in 1 vs. 1 combat
• better tower defender (more time alive under turret means more damage by that tower)
• is able tank enemy tower
• Guardian Angel and Death Defied can make enemies angry (this build is named by that)
• many people focus Karthus as squishy mage even if he is a tank
• cc doesn't make him big trouble
• very funny to play

Disadvantages of " Karthus the Tank" against " Karthus the Mage":

• not as good teamfighter.... but still better than most champs; overmore teamfights are minor in Dominion
• drains mana like hell (lower dps + higher endurance = longer fights).... but Clarity and Frozen Heart
• harder to play (mana management and more - look the next chapter).... but you can learn
• low IQ people might scold you like "OMG! Karthus tank! N00b!!".... but you can show them this build xD

Passive: Death Defied

Description: When Karthus dies, he becomes ghost who can cast spells (but can't move) for 7 seconds. In this form Karthus can't be target of spells or abilities and is completely imune to attacks and/or AOEs (so his spells can't be interrupted). Spells casted in ghost form cost no mana.
Even if Death Defied is probably the best passive in whole game, you won't use it as much while you're a tank because you usually won't die. But when you see you are dying, try to fall directly under some capture-point to delay your enemies next seven seconds before capturing or neutralizing that point.


Q: Lay Waste

Description: Spell is targeted to a small area in quite long range. It damages all enemy units in affected area. If there is just one target, Lay Waste deals double damage.
There is no important difference between using Lay Wastes as " Karthus the Tank" or " Karthus the Mage". Just keep in mind that you have lower damage.


W: Wall of Pain

Description: Karthus conjures magic wall (the higher skill level the wider wall) for 7 seconds. Enemy magic resistance and movement speed is reduced for 5 seconds when he pass through the wall. Approximately 14secs cooldown (with some CDR - so basic cd is something about 17secs, I don't know exactly).
Use the Wall of Pain just like as " Karthus the Mage" with one little difference. When you are squishy, you can't put the wall into the right place sometimes because it's too dangerous (e.g. while your teammates retreat after ambush); you can do it better as a tank. Wall of Pain isn't affected by your AP.


E: Defile

Description: Toggle-type spell. When activated, it damages every enemy unit around Karthus (very nice range) each second and cost him quite lot of mana. When deactivated, it restores mana every time Karthus kills an unit. Area of effect is moving with it's caster - he is allways in the middle.
Cut down using of your Defile to minimum while you are a tank. Because of long fights (or long defending of whatever) you are extremely mana dependent. Rely on your Lay Wastes and save your mana. I follow the rule that my mana-bar shouldn't go under my health-bar by using Defile in any fight unless there is some good reason for it (e.g. low-HP enemy, returning to the base, critical situation around some capture-point, Clarity ready, ....). This -of course- requires skilled Karthus player who is able to kill by Lay Wastes.


R: Requiem

Description: After three seconds channel, this spell damages every living enemy champion in any distance. If channel is interrupted, spell is canceled and you have to wait till next cooldown before casting. Cooldown 180s / 150s / 120s (in late-game you can cast it approximately each 90 seconds due to CDR).
It doesn't deal as good damage since you're a tank. But you can interrupt all enemy channels in a time or finish off retreating enemies (this also requires some skill because they can easier heal and you need to calculate the true damage from magic damage fast because there is many situations where you don't know if you are able to kill).

This is a must for " Karthus the Tank". He drains mana as hell because all fights are much longer when Karthus is a tank. You will face mana-problems all the game without AP. Clarity can help you (early more than late but it helps anyway).



Ghost is great spell for Dominion. Movement speed is the key to victory. There are so many situations when you need to be faster than you are. This spell is really gamechanging.
You can -of course- use it for chasing or running out but I see the main potential of this spell in reaching the capture-point as fast that you can turn it into your turret before the enemy comes.

I start with Mobility Boots, Cloth Armor, Mana Potion and Health Potion. Then I build Guardian Angel followed by Frozen Heart. Afterwards I buy Warmog's Armor, Force of Nature and I finish by Thornmail (or Banshee's Veil in some extreme cases).

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I prefer Mobility Boots over Sorcerer's Shoes in Dominion. Although magic penetration is good for killing, I consider fast movement and map control as much more important than combat advantages. Due to higher initial gold it's possible to buy this item immediately after the start.

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This is only tanky item you can buy after Mobility Boots. Overmore, you spend all your starting money after buying Mobility Boots, Cloth Armor, Mana Potion and Health Potion. After you earn some more gold, you can build Guardian Angel from Cloth Armor.

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Although Karthus' mana pool is very big and Mana Potion doesn't mean a lot for him, it can give you some more time on the battlefield (which you can't earn by your Defile because of creeps lack).

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Every more second you can spend on the battlefield instead of returning to the base can win you the game. Health Potions are cheap and gives you some time out of your base in early-game.

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I build Guardian Angel as my first tanky item because it gives armor, magic resistance and it's passive is great for get enemies angry. I call that "old good trick with ghost and wings" (ghost refers to Death Defied and wings refers to Guardian Angel) and name of this build refers that. If there is Zilean in your team (which is not likely in Dominion), you can upgrade your trick by Chronoshift to be able to kill even after three deaths which is upgraded fun xD. Although you can use Guardian Angel's passive just once in every five minutes which is quite long in Dominion, it is still the best armor + magic resist item.

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Good tanky and supporting item with CDR. I would maybe buy Frozen Heart later if I was in better mana situation but 500 mana is exactly what you need.

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After armor and magic resist you need more health to make yourself more resilient. Regeneration is also good in Dominion because you can refresh your health without going base (if you aren't on very low health, of course) which is always handy.

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More health regen, the highest magic resist in the game AND -first of all- movement speed! Great tank-item in Dominion.

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OR
I choose my last item between Thornmail and Banshee's Veil which is mostly quite easy choice.

Thornmail: Great item to counter ADs. There are many ADs in Dominion and your problems are mostly caused by them, buy Thornmail.

Banshee's Veil: Very good defensive item which gives you some more mana that you need. If there is equation between enemy AP and AD damage, buy Banshee's Veil instead of Thornmail but there is mostly AD superiority.

I keep my standard Dominion masteries even if I play " Karthus the Tank". It's good for first fighting when I am still pure mage (before I buy something tanky instead of AP). Why 9-0-21? 21 in utility because there is Swiftness , Transmutation , Mastermind and Intelligence .... the main reason is Swiftness anyway. 9 in attack because you can use 9 points much better in offense than in defence ( Arcane Knowledge is great).

Glyphs: Greater Glyph of Scaling Cooldown Reduction lower your cooldowns which makes you able to cast Requiems frequently AND also faster your Wall of Pain which is good cc for a tank. Flat bonus instead of per level is here because of fast leveling in Dominion (and starting at third level). Overmore, there is no blue buff in Dominion so you can't reduce your cooldowns by blue buff.


Marks: You are good damage dealer even if you're a tank and there are no better marks than Greater Mark of Magic Penetration.

Greater Seal of Vitality
Seals: Health is good for every tank. Flat bonus instead of per level bonus because heroes starts at third level in Dominion.


Quintessences: Great runes for Dominion; speed is the key to victory on this map.

To fully understanding " Karthus the Tank" in Dominion, you must firstly understand standard Karthus Summoner's Rift AP build and Karthus Dominion AP build. Read my guides and play it before you start to play this. Furthermore, you need to understand tanking as such.
Tanking in Dominion is quite easy because teamfights are mostly clearly positioned (around the capture-points) which makes initializing easy to handle. Overmore, there are not so many squishy characters in Dominion; it makes your tank-job even easier.
While playing " Karthus the Tank", keep in mind that you are a tank as well as mage (with low damage output) but your playstyle should respond to tank: you can tank turrets, you can initialize etc.
Proper using of your spells you can (in theory) learn here and here. Tanking skill is very difficult in Summoner's Rift but quite easy in Dominion; just tank towers if it's necessary.

Even tanks can score a quadra kill:

Thank you for reading my build, I hope you like it.

I will be glad for every meaningful comment; point out my errors (even that gramaticals), I will correct it (if I will agree with you; otherwise we can discuss that).