Matchup
Build vs Karthus
Build adapted to this matchup
Starting items
Core build
Standard
Summoner spells
75%
15%Anti AD
Anti CC
Anti Tank
Other options
Inspiration
Glacial Augment
Hextech Flashtraption
Biscuit Delivery
Cosmic Insight
Sorcery
Celerity
Nimbus Cloak
Power Spikes
Strength by game phase
Blitzcrank
KarthusKarthus's abilities
Passive, spells and ultimate
Upon dying, Karthus enters a spirit form that allows him to continue casting spells.
Cooldowns
Cooldowns by spell rank
| Level | Q | W | E | R |
|---|---|---|---|---|
| 3 | 0s | 15s | 0.5s | – |
| 6 | 0s | 15s | 0.5s | 3m20 |
| 9 | 0s | 15s | 0.5s | 3m20 |
| 11 | 0s | 15s | 0.5s | 3m |
| 16 | 0s | 15s | 0.5s | 2m40 |
| 18 | 0s | 15s | 0.5s | 2m40 |
Playing against Karthus
How to counter and exploit weaknesses
Zhonya's, Edge of Night, and Banshee's block/cancel his R — buy one of these items if Karthus focuses you.
His Q deals double damage on isolated targets: stay in your minions or near allies to split the damage.
Shields, Soraka R, and heals can counter his R if well-timed — save an emergency heal for Requiem.
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 9, 2026