Matchup

Senna
Senna
54%
46%

vs

41.2%

over 238 games

Karthus
Karthus
17%
83%
Heavy AP damageCountered by stasisSustained DPSHigh burst

Hard matchup

Build vs Karthus

Build adapted to this matchup

Starting items

Doran's Blade
Health Potion

Core build

Tear of the Goddess
1
Hubris
2vs Tank
Muramana
3

Standard

Boots of Swiftness
4vs Slow
Statikk Shiv
5DPS

Summoner spells

42188%
146%

Anti AD

Plated Steelcaps
4vs AD
Guardian Angel
5vs AD

Anti Heal

Mortal Reminder
6vs Hybride

Anti AP

Mercury's Treads
4vs CC
Maw of Malmortius
5vs AP
Wit's End
vs AP
Kaenic Rookern
vs AP

Anti Tank

Black Cleaver
5vs Tank
Lord Dominik's Regards
vs Tank
Voltaic Cyclosword
vs Tank
Edge of Night
vs Tank
Youmuu's Ghostblade
vs Tank
The Collector
vs Tank

DPS

Statikk Shiv
DPS
Hexoptics C44
DPS
Infinity Edge
DPS
Dusk and Dawn
Mage tank
Rapid Firecannon
DPS
Blade of The Ruined King
DPS
Phantom Dancer
DPS
Stormrazor
DPS
Bloodthirster
DPS
Runaan's Hurricane
DPS
100.0% WR2 games
PrecisionPrecision
Fleet FootworkFleet Footwork
Presence of MindPresence of Mind
Legend: AlacrityLegend: Alacrity
Cut DownCut Down
SorcerySorcery
Manaflow BandManaflow Band
CelerityCelerity
Attack SpeedAdaptive ForceHealth

Power Spikes

Strength by game phase

Early (0-15)
Mid (15-30)
Late (30+)
SennaSenna
KarthusKarthus
Careful
Careful
Aggressive

Karthus's abilities

Passive, spells and ultimate

Death Defied (P)

Upon dying, Karthus enters a spirit form that allows him to continue casting spells.

Cooldowns

Cooldowns by spell rank

LevelQWER
30s15s0.5s
60s15s0.5s3m20
90s15s0.5s3m20
110s15s0.5s3m
160s15s0.5s2m40
180s15s0.5s2m40

Playing against Karthus

How to counter and exploit weaknesses

1

Zhonya's, Edge of Night, and Banshee's block/cancel his R — buy one of these items if Karthus focuses you.

2

His Q deals double damage on isolated targets: stay in your minions or near allies to split the damage.

3

Shields, Soraka R, and heals can counter his R if well-timed — save an emergency heal for Requiem.

4

Karthus is immobile and squishy — dive him quickly to eliminate him before he deals continuous damage.

Source: op.gg + LTL Engine · Patch 16.9.1 · May 8, 2026