Champions › Karthus
Karthus Jungle Build, Patch 26.20 — Runes, Ability Damage & ARAM Buffs/Nerfs
the Deathsinger · AP damageMageBattlemageJungle
Every number below is computed from Riot's official game data for patch 26.20 — the Worlds 2026 patch (Data Dragon, with Meraki Analytics ability values and Riot's published ARAM balance), not sampled from match histories. Open the interactive labs to test Karthus against any opponent at any level.
Damage LabLaning matchupBuild LabARAM sheet
Karthus build and runes (Jungle, patch 26.20)
Item order
- Rabadon's Deathcap
- Spellslinger's Shoes
- Zhonya's Hourglass
- Shadowflame
- Dusk and Dawn
- Riftmaker
Start: Doran's Ring, Health Potion
Situational: —
Rune page
Domination · keystone Electrocute
Cheap Shot, Sixth Sense, Treasure Hunter
Secondary: Axiom Arcanist, Transcendence
Summoners: Flash, Ignite · Skill order: Q > E > W
Karthus is classified AP from its ability scalings; itemization computed from Rabadon's Deathcap + current-patch item stats. Win-rate shown is an estimate and does not drive the build.
Karthus base stats by level
| Level | Health | Attack damage | Armor | Magic resist | Attack speed |
|---|---|---|---|---|---|
| Level 1 | 620 | 46.0 | 21.0 | 30.0 | 0.625 |
| Level 6 | 1,054 | 58.8 | 39.6 | 35.1 | 0.677 |
| Level 11 | 1,585 | 74.5 | 62.2 | 41.4 | 0.741 |
| Level 18 | 2,490 | 101.2 | 100.9 | 52.1 | 0.849 |
Growth follows Riot's per-level curve: value = base + growth × (n−1) × (0.7025 + 0.0175 × (n−1)).
Karthus ability damage per rank
Q — Lay Waste magic
| Rank | R1 | R2 | R3 | R4 | R5 |
|---|---|---|---|---|---|
| Base damage | 40 | 59 | 78 | 97 | 116 |
| Cooldown (s) | 1.0 | 1.0 | 1.0 | 1.0 | 1.0 |
Scaling: 35/35/35/35/35% AP.
Karthus Q damage by champion level (own stats, no items)
| Level | Rank | Raw damage | Cooldown |
|---|---|---|---|
| Level 1 | rank 1 | 40.0 | 1.0s |
| Level 3 | rank 2 | 59.0 | 1.0s |
| Level 6 | rank 3 | 78.0 | 1.0s |
| Level 9 | rank 5 | 116.0 | 1.0s |
| Level 11 | rank 5 | 116.0 | 1.0s |
| Level 13 | rank 5 | 116.0 | 1.0s |
| Level 16 | rank 5 | 116.0 | 1.0s |
| Level 18 | rank 5 | 116.0 | 1.0s |
W — Wall of Pain none
| Rank | R1 | R2 | R3 | R4 | R5 |
|---|---|---|---|---|---|
| Base damage | no direct damage | ||||
| Cooldown (s) | 15.0 | 15.0 | 15.0 | 15.0 | 15.0 |
Scaling: no scaling.
E — Defile magic
| Rank | R1 | R2 | R3 | R4 | R5 |
|---|---|---|---|---|---|
| Base damage | 8 | 12 | 18 | 22 | 28 |
| Cooldown (s) | 0.5 | 0.5 | 0.5 | 0.5 | 0.5 |
Scaling: 5/5/5/5/5% AP.
Karthus E damage by champion level (own stats, no items)
| Level | Rank | Raw damage | Cooldown |
|---|---|---|---|
| Level 1 | rank 1 | 7.5 | 0.5s |
| Level 3 | rank 2 | 12.5 | 0.5s |
| Level 6 | rank 3 | 17.5 | 0.5s |
| Level 9 | rank 5 | 27.5 | 0.5s |
| Level 11 | rank 5 | 27.5 | 0.5s |
| Level 13 | rank 5 | 27.5 | 0.5s |
| Level 16 | rank 5 | 27.5 | 0.5s |
| Level 18 | rank 5 | 27.5 | 0.5s |
R — Requiem magic
| Rank | R1 | R2 | R3 |
|---|---|---|---|
| Base damage | 200 | 350 | 500 |
| Cooldown (s) | 200.0 | 180.0 | 160.0 |
Scaling: 70/70/70% AP.
Karthus R damage by champion level (own stats, no items)
| Level | Rank | Raw damage | Cooldown |
|---|---|---|---|
| Level 6 | rank 1 | 200.0 | 200.0s |
| Level 9 | rank 1 | 200.0 | 200.0s |
| Level 11 | rank 2 | 350.0 | 180.0s |
| Level 13 | rank 2 | 350.0 | 180.0s |
| Level 16 | rank 3 | 500.0 | 160.0s |
| Level 18 | rank 3 | 500.0 | 160.0s |
Karthus ARAM buffs & nerfs (Howling Abyss balance modifiers)
Karthus deals -7% damage and takes +5% damage on the Howling Abyss.
| ARAM modifier | Value |
|---|---|
| Damage dealt | -7% |
| Damage taken | +5% |
| Healing | — |
| Shielding | — |
| Attack speed | — |
| Ability haste | — |
| Tenacity | — |
| Energy regen | — |
ARAM also starts champions at level 3 with 1,400 gold. The ARAM sheet applies these modifiers to every stat and ability side by side with Summoner's Rift.
Frequently asked
What is the best Karthus build on patch 26.20?
RiftLab's stat-driven build for Karthus Jungle is Rabadon's Deathcap, Spellslinger's Shoes, Zhonya's Hourglass, Shadowflame, Dusk and Dawn, Riftmaker, with Electrocute as the keystone. It is computed from the champion's damage profile and the opponent's resists, not from win-rate scraping.
Does Karthus have ARAM modifiers?
Yes. On ARAM Karthus deals -7% damage and takes +5% damage.
How much damage does Karthus's Lay Waste do?
Karthus's Q (Lay Waste) has a base damage of 40/59/78/97/116 across its ranks and scales with 35/35/35/35/35% AP. Before the target's resistances; use the Damage Lab for the mitigated number against a specific opponent.
How much health does Karthus have at level 18?
Karthus has 2,490 base health, 100.9 armor and 52.1 magic resist at level 18 with no items, on patch 26.20.
Data: Riot Data Dragon 26.20, Meraki Analytics, LoL Wiki ARAM table. Builds are stat-driven recommendations from RiftLab's optimizer, not win-rate aggregates.