Hi! I’m Aqua Dragon. I ended Season 4 at Master 1 and I play Tank Karthus on my ranked smurf, and am also the co-creator of www.bestbans.com !
I also play: then make guides on them!
Keep in mind this is not meant to be an exhaustive guide. It is meant to outline the basic principle, items, runes, and playstyle of Tank Karthus. As such, I won't be delving into why certain customization choices were made. However, my hope is that I will have explained Tank Karthus enough that my rationale will be a self-evident extension, and to also allow you to make personal customizations as well.
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Pros and Cons
- Moves very fast; easily sticks to opponents
- Incredible mana sustain during laning
- Powerful initiator
- Strong early kill potential
- Great roam during laning phase
- Weak waveclear
- Devours mana rapidly
- No inherent tankiness
- No inherent health sustain
- Low AP; ultimate is weak
What is Tank Karthus?
Karthus is most known for amassing massive AP, sacrificing themselves into the fray to do massive burst damage with Defile, and cleaning opponents with a half-health chunking Requiem. However, it turns out Karthus is able to viably become a more sustained-damage tank that trades off the chunking power of the ult to become a combination of Swain and Singed during teamfights.
This is possible because Karthus only has a great AP ratio on Requiem. It is fairly lackluster on Lay Waste and Defile. The AP ratios of each spell are:
--Lay Waste (Single): 0.6
Lay Waste (Multiple): 0.3
Though the 0.6 scaling on Lay Waste is nice, it only applies when hitting a single target. This is largely only feasible during laning. In teamfights it's far more likely to only get multi-hit Lay Wastes unless Karthus is chasing someone down.
To be fair, both Defile and Lay Waste hit every second, making the low AP ratio more valuable. But also to be fair, it's a bit deceptive to look at the damage of high second-applying AP ratios without measuring it in a "damage otherwise done" way. By that I mean, let's compare two Karthuses. One with 300 AP and one with 0 AP.
With Defile active for 5 seconds, at rank 5, the 0 AP Karthus will deal 550 damage. the one with 300 AP will deal 850 damage. This is only a 300 damage difference, meaning a Tank Karthus would only have to live for 3 extra seconds compared to AP Karthus to make up the difference. So while the raw damage AP Karthus can deal is much higher, the difference in damage compared to Tank Karthus is only marginally higher by comparison, and often can be more than made up for by living in fights so much longer and freely positioning
This means that getting AP is primarily useful for Requiem, not for the other spells. However Requiem is on an impressively long cooldown and there are an amazing number of ways to nullify its damage. Instead of banking most of the damage into Requiem, could power be transferred away into the rest of the kit? Tank Karthus answers this question with a resounding yes.
Tank Karthus does this by abusing the base power of Defile. A standard AP Karthus tries to abuse the scaling on single-hit Lay Wastes to do damage, but this creates unreliability in the damage output. In addition, maxing Lay Waste first prevents the surprising power of Defile from being abused.
Each level of Defile is on par in damage with its equal-level Lay Waste counterpart. This is to say, a Level 3 multi-hit Lay Waste does non-guaranteed 80 damage. A Level 3 Defile does 70 largely-guaranteed damage in an AOE. Thus, maxing Defile first is like hitting your opponent with a non-amplified Lay Waste every second. This isn't strictly true and has nuance, but the principle is the point.
There's good reason Defile isn't used this way. Its high mana drain is, well, draining. In addition, putting yourself into range of its use is extremely dangerous for the fragile Karthus.
This is where Tank Karthus comes in. Because Tank Karthus doesn't have to focus on AP items, they are able to focus more heavily on maximizing a mana pool and building survivability to make amazing use of Defile. This is combined with high mobility/slows from Righteous Glory, Ghost, Wall of Pain, and Exhaust to make Karthus stick to the enemies and whittle them down Singed-style.
Because of this, you will often end up doing the most damage out of everyone in the game, even comparable to a full AP Karthus. Your damage will be more sustained by comparison and suffers the disadvantages of the damage style, but your presence in fights still demands respect.
Soul Build Order
Tank Karthus' playstyle favors stickiness and abusing Defile. This means Mana and mobility are top priorities for Karthus. Resistance and Magic Penetration are the next priorities as they make the prior stats worthwhile.
High resistance runes and items are preferred to make up for Karthus' lack of inherent tankiness. Finally, AP is a tertiary priority, meaning it is largely not the focus of the build.
Since AP is not the primary goal of the build, Doran's Ring is excessive. The early levels in Defile also provide sufficient mana sustain.
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Consider getting two ruby crystals when up against especially brutal matchups or against assassins.
After building the cores, follow up with three situational items.
Try to avoid building Liandrys until you have at least two heavy defensive items, and even then you should consider getting a third defensive item instead. It is best when against compositions with only one damage type.
Stage of the Game
In the early game, your goals are to
- Farm waves from a distance
- Dive opponents regularly with Defile and force summoner spells
- Replenish mana between these attacks with Defile's mana regen
Ghost and Exhaust are on especially short cooldowns and should be abused to get early kills on overextending opponents. You easily outrun enemies, even if they have dashes. Don't be afraid to use both summoner spells at once to force their longer-cooldown summoners like Flash.
Each dive is heavily mana intensive. Early levels in Defile will provide a quick way to get more mana as you prepare for the next tackle. Be aware that using Lay Waste to farm will not return nearly as much mana as farming with autos, so avoid relying on it when you can.
Feel free to harass a little with Lay Waste, but realize it won't do an amazing amount of damage and eats up mana that could otherwise be saved for Defile tackles.
You can start roaming very early on due to the powerful engage that Ghost provides. When your opponent has left lane, run over to other lanes and use Ghost to ambush unsuspecting opponents.
It's sometimes better not to use Lay Waste during defile tackles, as the mana cost expends a second of Defile's time. Unless you know for sure that you'll land the hit, let Defile do the brunt of the work.
You usually shouldn't bother leveling Wall of Pain until level 7. It has an exorbitant mana cost and the slow it provides isn't as strong as simply getting earlier points in Lay Waste and Defile.
As the laning phase ends, you will start taking on a more aggressive role.
- Initiate fights with Ghost, Wall of Pain, and Righteous Glory
- Pick a target in the fight and stick to them
- Chase down lonely opponents and kill them
- Use Requiem to clean up easy kills
You must not be afraid to dive headlong into the fray. You are the one who decides when fights happen due to the enormously powerful initiation. Lead the charge.
Opponents who barely escape from your defile tackles can be shot down with Requiem. Take note however that Tank Karthus' Requiem is not too strong. Keep tabs on its base damage and use that number to figure out when it's time to ult.
Your dueling power is fairly respectable. If you see someone extending too far to push or too far in your jungle, use your superior mobility with Exhaust to defile them down.
You move pretty fast and are tanky, but that's no reason to take free hits. Try to skirt melee enemies at the edge of your defile instead of always standing right next to them.
Once you're out of mana, you're spent. You have no real mana regeneration outside of lane. Be cautious of your mana bar to make sure you won't overexert yourself before battles are truly done.
You retain a similarly sticky role as the game reaches its conclusion
- Build defensive items for the situation
- Make picks on lonely opponents with your mobility
- Try to attract the attention of as many opponents as possible in fights
Continue to start fights when you see openings. You remain the dictator of when fights begin.
Thornmail is especially powerful on Karthus. It's easy to get into close range of ADC's. Once Thornmail nullifies their lifesteal, their death becomes guaranteed, especially with an Exhaust. If you can force the ADC away by yourself, you can gain an immense fighting advantage for your team.
Your Lay Waste will start packing a bit of a hit now. Feel free to spam it for offense, though be mindful of your mana.
This guide was a lot of fun to write, and I hope you all have learned everything you would have liked. If you have any questions, leave a comment or drop a line over at twitch.tv/aquadragon33 ! And be sure to check out www.bestbans.com !
Bring a Glorius end.