Consistent lane pressure and item efficiency.
Empowered abilities and resource manipulation
Hitting a champion with spells hurls a comet that deals adaptive damage at them. Landing more spells reduces Arcane Comet's cooldown.
Gain cooldown reduction and max cooldown reduction on your ultimate. This is increased further each time you use your ultimate, up to a maximum.
Gain 10% CDR when you reach level 10. Excess CDR becomes AP or AD, Adaptive.
Your first ability hit every 20s burns champions.
+20 Ability Power or +12 Attack Damage, Adaptive
Gain a free stopwatch. Stopwatch has a one time use Stasis active.
+5% Max CDR
+5% Summoner Spell CDR
+5% Item CDR
Arcane Comet has a low cooldown allowing Ahri to proc it repetitively in lane for harassment damage.
Ahri's ultimate grants her incredible kill potential and lane safety. Having it off cooldown as often as possible is fantastic for her.
Transcendence is a great rune choice for most mages as repetitive spell casts is the majority of their damage, and pairs well with Ultimate Hat.
Scorch is a rune that is incredibly reliable and provides the damage needed to eek out lane dominance.
Perfect timing is a great option on Ahri who often wants Zhonyas as she tends to dive in for her damage. It also secondarily acts as a pure gold, saving you the cost of an item component.
Cosmic Insight is an all-around fantastic rune choice for Ahri. The extra bit of CDR lets you get out more damage in trades and teamfights.