Karthus ARAM Mayhem Build

The Deathsinger. A below-average pick in ARAM Mayhem on patch 26.21: #120 of 173 champions.

CPatch 26.21MageNo runes in Mayhem

Tier: C
Win rate: 48.0%
Pick rate: 11.4%
Rank: #120 of 173
Games: 2,634,454
Patch: 26.21

How to play Karthus in ARAM Mayhem

Karthus is a below-average pick in ARAM Mayhem on patch 26.21: tier C, #120 of 173 champions, with a 48.0% win rate over 2,634,454 games. It is also one of the most picked champions, showing up in 11% of games, so expect to see it on both sides.

89% of Karthus's damage to champions is magic, so enemy magic resist is what slows it down. It deals 58,203 damage to champions in an average game, more than most champions, so play to stay alive and keep hitting. It dies 16.2 times per game on average: it trades its life for impact, so time your engages with your team.

The AP build, ability power items, is both the most played and the top-ranked path: Blackfire Torch, Liandry's Torment and Shadowflame, with a 48.1% win rate over 2,108,387 games. On this build 88% of players skip boots and spend the slot on another item.

The cards that do best on Karthus are Blue Barrier, Erosion and From Beginning To End. Cards built around ability power fill most of the top of its list, followed by attack damage. Skip Don't Change the Channel and Ultimate Awakening when you can: they do worst on Karthus. A pair to look for: Phenomenal Evil with Blue Barrier.

Take Flash and Mark (93% of players). Max Q (Lay Waste) first, then E, then W. Players who max E first instead win a little more often, so it is worth trying.

Karthus ARAM Mayhem build

ARAMKit groups every Karthus game by build path. The top-ranked path comes first, with the items most players start with, buy first and add later.

AP build · top ranked

48.1% win rate · 86% of Karthus games · 2,108,387 games

Start

Amplifying Tome
Fated Ashes

Core items, in buying order

Blackfire Torch
Liandry's Torment
Shadowflame

Boots on the AP build for Karthus, top ranked first, with the share of players who buy them
Boots, best first	Players
No boots	88%
Sorcerer's Shoes	10%

Situational, after the core

Stormsurge11% buy it
Rabadon's Deathcap72% buy it
Void Staff46% buy it
Malignance18% buy it
Horizon Focus4% buy it
Rylai's Crystal Scepter4% buy it

Most bought items

Shadowflame79% of games
Rabadon's Deathcap68% of games
Malignance66% of games
Blackfire Torch63% of games
Liandry's Torment59% of games
Void Staff35% of games
Stormsurge22% of games
Horizon Focus16% of games
Sorcerer's Shoes11% of games
Cryptbloom10% of games

Best augments for Karthus

Every card with enough Karthus games, by tier and best first within each tier. Tiers are Karthus's own: a card can be S tier here and C tier on another champion. As Riot's policy asks, cards are shown by tier and order only, never with a win rate. Click a card for its own page; the augment tier list ranks them over all champions.

PrismaticBest prismatic cards

1GoldrendTier S
2Clown CollegeTier S
3Giant SlayerTier S

GoldBest gold cards

SilverBest silver cards

S- and A-tier cards for Karthus

9 S tier and 22 A tier, best first.

The S- and A-tier augments for Karthus in ARAM Mayhem, best first, with their rarity and what they do
Augment	Rarity	Tier	What it does
Blue Barrier	Silver	Tier S	Gain 200–450 (by level) % of the Max Mana Mana you spend as a Shield for 1.5 seconds. Shields up to 300–800 (by level)
Erosion	Silver	Tier S	Damaging enemies shreds 1.5% Armor and Magic Resist for 4s, up to 30% at 20 stacks.
From Beginning To End	Gold	Tier S	Gain the First Strike and Dark Harvest Keystone Runes. First Strike: When you initiate champion combat, deal 10% extra damage for 3 seconds…
Goldrend	Prismatic	Tier S	Damaging a champion with Attacks or Abilities deals an additional (50–150 (by level) +20% Ability Power +40% Bonus Attack Damage) magic…
Phenomenal Evil	Gold	Tier S	Permanently gain 1 Ability Power when you damage enemy champions with Abilities. If taken as your second Augment, starts with 40 Ability…
Clown College	Prismatic	Tier S	Backstab: You deal (20–35 (by level) +35% Ability Power +50% Bonus Attack Damage) bonus physical damage when striking from behind. Deceive…
Forged By The Master	Silver	Tier S	Your Item and Augment damage are increased by 45%.
BEES!!!	Gold	Tier S	Every 15–10 (by level) seconds, your next Ability hit against an enemy champion throws a beehive at the target. Upon arriving, the hive…
Giant Slayer	Prismatic	Tier S	Become tiny, gain 20% Movement Speed, and deal between 10% and 30% bonus damage to champions based on how much larger they are than you.
Weapon of Destiny	Gold	Tier A	Your first Legendary Item becomes the Weapon of Destiny. When a champion you damaged within the last 3 seconds dies, increase the Weapon of…
Ultimate Revolution	Prismatic	Tier A	Refresh your Ultimate after casting it (75 seconds Cooldown or reset on death).
From Downtown	Gold	Tier A	QUEST: Snipe 15 enemy champions with abilities. Snipe - Damage enemies over 600 distance away. REWARD: A meteor flies at enemy champions you…
Dive Bomber	Silver	Tier A	Explodes when you die, dealing 20% of the target's max Health as true damage to nearby enemies.
Upgrade Stormsurge	Gold	Tier A	Stormsurge's Squall now always detonates in an area, dealing (10%+2% Ability Power) maximum Health magic damage to all nearby enemies. Enemy…
Get Jinxed	Gold	Tier A	Replace a Summoner Spell with Get Jinxed! Get Jinxed!: Ride a rocket that explodes upon hitting an enemy champion, structure, or terrain…
Twin Fire	Silver	Tier A	On ability damage, fire 1 plus (3% Critical Strike Chance) missiles that deal (10–30 (by level) +7% Bonus Attack Damage+7% Ability Power)…
Hand of Baron	Prismatic	Tier A	Gain 25% Adaptive Force. Nearby allied minions are greatly empowered.
Pursuit of Power	Gold	Tier A	QUEST: Hit enemy champions with selected ability 10 times. REWARD: Permanently increase selected ability damage by 30%.
Back To Basics	Prismatic	Tier A	Your Ultimate Ability is sealed. Gain 35% Ability Damage, Healing, Shielding, and 70 Ability Haste.
Jeweled Gauntlet	Prismatic	Tier A	Your Abilities can Critically Strike for 45% increased damage. Gain Critical Strike Chance (25%+4.5% Ability Power) Crit Chance.
Eureka	Prismatic	Tier A	Gain (30% Ability Power) Ability Haste.
Totentanz	Prismatic	Tier A	Replace a Summoner Spell with A Dance with Death. A Dance with Death: Become Unkillable for 5 seconds and blink forward. If you get a…
Biggest Snowball Ever	Prismatic	Tier A	Gain 100 Ability Haste on Snowball. Your snowball is BIG and will pass through minions. It Slows enemies for 20% for 2 seconds, Knocks Up…
Big Brain	Gold	Tier A	Gain a (300% Ability Power) Shield. Resets on death or 70 seconds after depletion.
Infernal Conduit	Prismatic	Tier A	Your Abilities apply an infinitely stacking Burn, dealing (2–20 (by level) +1.2% Ability Power +2.8% Bonus Attack Damage) magic damage per…
Wooglet's Witchcap	Prismatic	Tier A	QUEST: Possess Rabadon's Deathcap and Zhonya's Hourglass. REWARD: Get Wooglet's Witchcap.
En Passant	Prismatic	Tier A	Periodically identify Vitals on enemy champions. Hitting Vitals with Attacks or Abilities deals an additional 6% + 1.5% per stack max Health…
Upgrade Zhonya's	Silver	Tier A	Reduce Zhonya's Hourglass Cooldown to 45 seconds. You can now move when in Zhonya's Hourglass, Seeker's Armguard, or Wooglet's Witchcap…
Homeguard	Silver	Tier A	Gain 100% Movement Speed, disabled for 6 seconds after taking damage.
Infinite Recursion	Prismatic	Tier A	Gain 60 Ability Haste, plus 3 Ability Haste per takedown.
Ok Boomerang	Gold	Tier A	Autocast a boomerang at a nearby enemy every 7 seconds, dealing (40–200 (by level) +30% Bonus Attack Damage+20% Ability Power) adaptive…

Average on Karthus
48 cards, best first

Below average on Karthus
20 cards, best first

Weakest on Karthus
11 cards, best first

Best first augment for Karthus

Your first card decides the early fights, and a card that is great as a first pick can be a weak fourth. ARAMKit ranks Karthus's cards for each pick on its own; these are the top five per pick, with their tier in that pick. For the first pick, Blue Barrier, Erosion and Weapon of Destiny come out on top.

The best augments for Karthus in each pick of an ARAM Mayhem game, best first, with their tier in that pick
#	First pick	Second pick	Third pick	Fourth pick
1	Blue BarrierTier S	Blue BarrierTier S	Blue BarrierTier S	Blue BarrierTier S
2	ErosionTier S	ErosionTier S	ErosionTier S	Ultimate RevolutionTier S
3	Weapon of DestinyTier S	Clown CollegeTier A	Forged By The MasterTier S	Upgrade StormsurgeTier S
4	Forged By The MasterTier S	From Beginning To EndTier A	Clown CollegeTier S	BEES!!!Tier S
5	Phenomenal EvilTier S	GoldrendTier A	Ultimate RevolutionTier S	ErosionTier S

Strong card pairs

Two cards that do especially well together on Karthus, best pair first.

Summoner spells and skill order

Summoner spells

Flash + Mark93% of players · 48.1% win rate
Ignite + Mark1% of players · 47.4% win rate
Ghost + Mark0% of players · 47.3% win rate

Skill order

QLay Waste
EDefile
WWall of Pain

Max Q first. 72% of players use this order (47.6% win rate); put points in R whenever you can. Maxing E first (24% of players) wins 49.5%.

Karthus in an average Mayhem game

Averages per game over every game on this patch.

K / D / A: 12.2 / 16.2 / 32.7
KDA: 2.93
Damage to champions: 58,203
Damage taken: 36,883
Self-mitigated: 16,989
Healing on allies: 45
Shielding on allies: 1
Crowd control: 27 s
Kill participation: 75%
Game length: 17:53

Damage type

Physical 1%Magic 89%True 10%

Questions and answers

What is the best Karthus build in ARAM Mayhem?

On patch 26.21 ARAMKit ranks the AP build first for Karthus: Blackfire Torch, Liandry's Torment and Shadowflame. It is also the most played build.

What are the best augments for Karthus in ARAM Mayhem?

The S-tier cards for Karthus, best first: Blue Barrier, Erosion, From Beginning To End, Goldrend and Phenomenal Evil. The full list by tier is on this page.

Is Karthus good in ARAM Mayhem?

Karthus is tier C on patch 26.21, #120 of 173 champions, with a 48.0% win rate over 2.6 million games. That makes it a below-average pick in ARAM Mayhem right now.

What is the best first augment for Karthus in ARAM Mayhem?

For Karthus's first pick on patch 26.21: Blue Barrier, Erosion, Weapon of Destiny, Forged By The Master and Phenomenal Evil, best first. Cards rank differently in later picks; the table on this page has all four.

Other Mages in ARAM Mayhem

Get Karthus's build and card tiers in your game

LazyElo is a free Windows app that sits next to the League client. In the Mayhem lobby it shows which champion on your bench is strongest; in the game you type the three cards you're offered and see their tier for Karthus side by side, with this build in the overlay.

Download LazyElo for Windows

Free plan, no ads. For Windows 10 and 11.

Plans and pricing The ARAM Mayhem overlay

ARAM Mayhem tier list
Every champion by tier on patch 26.21.
ARAM Mayhem augment tier list
Every card from S to D over all champions.
All Mayhem builds
Pick a champion from the full list.
ARAM Mayhem rules
Augment levels, rerolls and why there are no runes.
ARAM Mayhem guide
How the mode, the cards and the picks work.
Karthus counters
Its lane matchups on Summoner's Rift.
ARAM Mayhem overlay
The card picker and build in the app.

Source: ARAMKit, used with permission. Patch 26.21, 23,177,263 ARAM Mayhem games, data of October 28, 2026. Riot keeps Mayhem games out of its public match API, so these aggregates come from ARAMKit. Card tiers are shown without win rates, as Riot's developer policy asks.