On Hit__________________- I always build this for the extra attack speed. This is standard for most marksmen, and Ahri is practically a Marksmen with this build.- Doing percent health damage is extremely effective against tanks, especially combined with Guinsoo's Rageblade- This gives Ahri more of everything she needs. She does more on hit damage, has armor and magic penetration, and after 6 attacks she will apply on hit effects twice every 3 hits. This is a great item and easy to use since Ahri's charm and ultimate.- This provides great wave clear and will apply on hit effects to all enemies in team fights, making it extremely useful. Along with the attack speed, movement speed, and critical chance, it makes it a great item.- Provides more mobility when attacking and a shield when low health. With the decent attack speed, critical, and movement speed, this makes PD is a decent item.- Bloodthirster is good with Runaan's and will heal you up extremely fast and provide a shield before heading in for team fights. It also provides a large amount of AD making your auto attacks deal even more damage than they already do at this point.- Armor for survivability, more attack damage, and a revive. Overall a good item for Ahri since if her ultimate is up after she dies, she can instantly activate it again to start kiting again.- More attack speed, on hit damage, and magic resist make this a good option if they have a lot of AP. The healing from its passive can also be a useful bonus.- The QSS upgrade. Providing life steal, damage, magic resist, and a way of dealing with CC, this is overall a good item if they have AP and CC.Critical__________________- Standard item for any critical build on any champion.- AOE Autos for more damage. My favorite zeal upgrade on most champions due to the fast wave clear and potential to 1v2- Arguably the best defensive zeal upgrade due to the shield and extra speed from ghosting.- Another solid zeal upgrade due to having decent wave clear but also providing a little more damage to one target than Runaan's.- More burst to one target but less waveclear than Statikk Shiv or Runaan's. I don't build this often but it can be useful at times.- Lifesteal combined with AD just works super well for most critical builds. The extra shield is also super useful. A solid choice for a critical build.(upgrades) - If you're facing a tanky team comp then these are super useful for getting your autos to do decent damage. If they have a lot of healing, build Mortal Reminder, else build Lord Dominik's Regard.Muramana Build__________________- Well, it's in the build name. It provides mana for a mana hungry champion which allows you to spam abilities.- Provides more mana so you get more AD from Muramana and makes it so you don't have to worry much about mana. Combined with the AD, CDR, and Crit, it's a good choice.- It provides solid wave clear and can be useful in just about any situation.- Provides everything this build is missing. More crit, a shield, and attack speed.- Extra wave clear and damage.- More range on an auto that can deal significant damage due to this build having more AD instead of Attack speed than other builds.(upgrades) - Useful for getting through armor if they're tanky. Mortal Reminder if the enemies have a lot of healing, else Lord Dominik's Regard.- Provides more attack speed which this build doesn't have a ton of, and with the extra AD, Active ability, and passive percent health damage, it's probably a better option than Bloodthirster for a Muramana build.- if the enemy team isn't very tanky, this could be a better item because the extra lifesteal and AD.