Matchup

Jax
Jax
50%
50%

vs

48.0%

over 225 games

Cassiopeia
Cassiopeia
18%
82%
Heavy AP damageSustained DPSHeavy CC

Skill matchup

Build vs Cassiopeia

Build adapted to this matchup

Starting items

Doran's Shield
Health Potion

Core build

Trinity Force
1DPS
Wit's End
2vs AP
Zhonya's Hourglass
3vs AD

Standard

Boots of Swiftness
4vs Slow
Sundered Sky
5Bruiser

Summoner spells

41456%
41235%

Anti AD

Plated Steelcaps
4vs AD
Death's Dance
5vs AD
Guardian Angel
vs AD

Anti AP

Mercury's Treads
4vs CC
Maw of Malmortius
5vs AP
Kaenic Rookern
vs AP
Force of Nature
vs AP

DPS

Sundered Sky
Bruiser
Dusk and Dawn
Mage tank
Hextech Gunblade
Mage
Blade of The Ruined King
DPS
Riftmaker
Mage tank
Stridebreaker
Bruiser
Hextech Rocketbelt
Mage tank
Hullbreaker
Bruiser
Nashor's Tooth
DPS
Spear of Shojin
Bruiser

Other options

Sterak's Gage
Survival
Dark Seal
Quicksilver Sash
Zeke's Convergence
Tank
100.0% WR4 games
PrecisionPrecision
Lethal TempoLethal Tempo
TriumphTriumph
Legend: AlacrityLegend: Alacrity
Last StandLast Stand
ResolveResolve
UnflinchingUnflinching
Bone PlatingBone Plating
Attack SpeedAdaptive ForceHealth Scaling

Power Spikes

Strength by game phase

Early (0-15)
Mid (15-30)
Late (30+)
JaxJax
CassiopeiaCassiopeia
Neutral
Neutral
Neutral

Cassiopeia's abilities

Passive, spells and ultimate

Serpentine Grace (P)

All Move Speed bonuses are more effective on Cassiopeia.

Cooldowns

Cooldowns by spell rank

LevelQWER
33.5s24s0.75s
63.5s24s0.75s2m
93.5s22s0.75s2m
113.5s20s0.75s1m40
163.5s16s0.75s1m20
183.5s16s0.75s1m20

Playing against Cassiopeia

How to counter and exploit weaknesses

1

Turn away when she casts her R: you'll be slowed instead of stunned if you're not facing her.

2

Her DPS depends on landing Q (poison) — if she misses Q, she can't effectively spam E.

3

W prevents dashes: do NOT dash into the zone, go around it.

4

Cassiopeia doesn't have boots — slows are particularly effective against her.

Source: op.gg + LTL Engine · Patch 16.9.1 · May 9, 2026