Flash : like every other champion does. It’s particularly importantand your life depend more on It,its the most important summoner spell which is an indispensable, you cannot not take it, you can use it to save your life, Dodge a spell cast or to protect someone on receiving damage that could kill him or to get closer to shield/heal him also to engage a fight.
Heal :This spell can be used to save a life when low on health and under attack. It is commonly used to get an early first blood by healing oneself for more than one's opponent expects. It is also a skill used for "baiting", where you make your champion appear weaker than it actually is to lure your enemies out of position or to get them to tower dive you. A similar baiting tactic is also commonly used withBarrier.
Barrier :is great for absorbing the burst of enemy champions or turret enhanced shots. Whether used on a squishy mid-laner or a tanky top-laner, a well-timed Barrier will help escape from tough situations.
Barrieris damage mitigating summoner spells, barrier is not affected by Grievous Wounds, has a shorter cooldown, blocks more damage (against a single target), and can be used while you're still at full health (good against 100-to-0 burst).
Exhaust :is used against the player that deal huge damage most are adc to slow their attack speed, attack damage and movement speed.
Ignite as your second spell if you think you can win your lane or can duel a healer champion in your lane.

Pros

Insane Burst Damage
The main reason why Ahri is one of the most powerful Mages is her insane burst damage. She can obliterate her target with just one simple combo.
Plus, with Electrocute, she can deplete the enemy’s health just with her Orb of Deception (1) and Basic Attacks.

Can Also Inflict True Damage
Aside from dishing out immense magic damage, Ahri’s Orb of Deception (1) also inflicts true damage when it flies back to Ahri. It certainly helps her to shred even the Tankiest opponents.

Has a CC with A Relatively Short Cooldown
Another thing that makes Ahri quite irritating in team fights is her CC, Charm (3). Her Charm not only has a long duration, but also a relatively short Cooldown.

High Mobility
Last but not least, Ahri also has high mobility due to her Fox Fire (2), which increases her Movement Speed. On top of that, Ahri can also pull off a triple dash with her Spirit Rush (Ultimate).

Cons

Sub-Par HP and Defense Base Stats
Since she’s a Mage, Ahri has terrible HP and defense base stats. It makes her squishy and can be killed easily by burst damage Champions like Zed or Lee Sin.

Long Ultimate Cooldown
Although Ahri’s Ultimate is very handy -inflicting enormous damage to nearby enemies and allowing her to dash for three times- this Skill has a relatively long Cooldown. It makes it difficult for Ahri to launch her combo and can only poke when she doesn’t have her Ultimate ready.

No Mobility When Flash and Ultimate Aren’t Available
Ahri relies heavily on her Ultimate and Flash as her escape tools. When both are on Cooldown, Ahri will find it significantly harder to escape from her opponents.

Sorcery

Summon Aery : empowers spells, autos, heals, and shields, making it a versatile Mid option for Malzahar. . Transcendence : Gain bonuses upon reaching the following levels: • Level 5: 5 ability haste. • Level 8: 5 ability haste. • Level 11: On champion takedowns, reduce the remaining cooldown of your basic abilities by 20%. this will help you reach maximum CDR or diversify their item path.more to get your ultimate ready faster because your ultimate is needed to lock the most dangerous enemy champ to engage all fights or protect your self or team mate. Manaflow Band : a staple rune which it helps to increase mana as early game as it works greatly with Archangel's Staff. Scorch : Scorch is a great rune pick which it burn the enemy for extra early game trade damage. Be careful when poking under tower, as it draw turrets agro to you.

Inspiration

Magical Footwear : it's an economic value makes it a strong rune on many champions, including Malz. Take free boots with better movement speed bonus. Biscuit Delivery : its a good potion that gives you some mana and regenerate your health to stay longer in the lane .

Ardent Censer : synergizes well with other healing and shielding sources, especially with those with either wide area of effect or with low cooldown. Also being able to deliver lot of on-hit effects increases the item's effect drastically.

Shurelya'sBattlesong's : mythic passive can grant up to 12.5% bonus movement speed with 5 other Legendary items. Shurelya'sBattlesong active provides great utility through the bonus movement speed, which can either help escape or chase. The damage empowerment allows allies to burst targets down.

Frozen Heart : is an item best suited for tank champions because of the high amount of armor and ability haste but can also be useful for tankysupport champions as both tend on be middle of enemy team during team fights this spreading the aura. Also works well with champions that desire ability haste, have mana problems and make very good use of the passive for extra dueling potential.

Rylai's Crystal Scepter Rylai's Crystal Scepter This item provide you HP and ability power as its buff your HP and gives you some AP damage and its Slow which it works greatly with you.

Banshee's Veil Banshee's Veil is a strong item against magic damage but is most valued for its ability to prevent crowd control or counter poke damage. As such it is highly recommended to build Banshee's Veil when you are being focused by crowd control effects, or when the enemy has initiation or pulling abilities it will make you very resilient to both magic and physical damage, During the late game, its a great addition for AP carries because it can block important crowd control abilities.

Zhonya's Hourglass Zhonya's Hourglass if you want to enjoy your damage you can build zhonya, you get 2 in 1 armor, cool down redcution and ability power. •Zhonya's Hourglass is most effectively used against abilities that have a downtime before they can affect the target ( Chum the Waters, Unleashed Power, Death Mark). • It is best used offensively and defensively with aura-type abilities ( Crowstorm, Soul Shackles) which do not require channeling. This is particularly powerful when used in the middle of the enemy team, allowing them to continue to deal damage as area of effect while being untargetable.

Rabadon'sDeathcap Rabadon's Deathcap is a powerful item for pure ability power casters, and is also very effective on burst assassins and hybrid champions Rabadon's Deathcap is essential for any champion with ability power ratios, tanky or carry, wishing to deal significant magic damage that will carry into late game.

Luden's Tempest Luden's Tempestmythic item good for wave clear and split pushing as its passive can grant up to 25 magic penetration with 5 other Legendary items. As its Dealing ability damage to an enemy deals bonus magic damage to your target and launches bolts at up to 3 enemies near them, dealing them the same damage, and grants you bonus movement speed for 2 seconds.

Morellonomicon Morellonomicon passive applies to all magic damage, regardless of their damage classification useful item against healers, With Liandry's Anguish the Grievous Wounds time can be extended for an additional 4 seconds.

Liandry's Anguish Liandry's Anguish mythic passive can grant up to 25 ability haste with 5 other Legendary items. TORMENT deals default damage, and thus will not trigger spell effects. TORMENT itself is not blocked by spell shield.

Demonic Embrace Demonic EmbraceAZAKANA GAZE: Dealing ability damage curses enemies, causing them to takepercent% of their maximum health as total magic damage as it works greatly with Liandry's Anguish.

Cosmic Drive Cosmic Drive If you want to have easy ability haste and ap damage this is a great itemif you have at least 160 ability power, gain 20 ability haste and bonus movement speed.