
Enchanter · magic (AP) damage
Later items show higher win rates partly because games that last that long are usually already being won. Compare items within a slot, not across slots.
Sorcery
Summon Aery
Arcane Comet
Deathfire Touch
Axiom Arcanist
Manaflow Band
Nimbus Cloak
Transcendence
Celerity
Absolute Focus
Scorch
Waterwalking
Gathering Storm
Resolve
Grasp of the Undying
Aftershock
Guardian
Demolish
Font of Life
Shield Bash
Conditioning
Second Wind
Bone Plating
Overgrowth
Revitalize
Unflinching

Based on 12,868 games · 52.3% win rate · High elo · patch 26.20.
Later items show higher win rates partly because games that last that long are usually already being won. Compare items within a slot, not across slots.
Sorcery
Summon Aery
Arcane Comet
Deathfire Touch
Axiom Arcanist
Manaflow Band
Nimbus Cloak
Transcendence
Celerity
Absolute Focus
Scorch
Waterwalking
Gathering Storm
Resolve
Grasp of the Undying
Aftershock
Guardian
Demolish
Font of Life
Shield Bash
Conditioning
Second Wind
Bone Plating
Overgrowth
Revitalize
Unflinching

Based on 91 games · 39.6% win rate · High elo · patch 26.20.

Janna's allies gain Move Speed moving towards her. Janna deals a portion of bonus Move Speed as bonus magic damage on hit and with Zephyr.

By creating a localized change in pressure and temperature, Janna is able to create a small storm that grows in size with time. She can activate the spell again to release the storm. On release this storm will fly towards the direction it was cast in, dealing damage and knocking away any enemies in its path.

Janna summons an air elemental that passively increases her Move Speed and enables her to pass through units. She may also activate this ability to deal damage and slow an enemy's Move Speed.

Janna conjures a defensive gale that shields an ally champion or turret from incoming damage and increases their Attack Damage.

Janna surrounds herself in a magical storm, throwing enemies back. After the storm has settled, soothing winds heal nearby allies while the ability is active.
Q Howling Gale
R MonsoonSlowignores tenacityFROM
W ZephyrSome of their lockdown (airborne) ignores tenacity, so you dodge it; you can't cleanse or Merc' through it.
Tap or hover a crowd-control type to see which ability it comes from.