Old post, but I'll answer it anyway. I'm an otp ahri 1 million mastery and the charm+flash is my bread and butter. There's 4 main reason to use it :
1) You want to cover a large distance rapidly. The best example I have is the fight for the crab in the river at lvl 3. You can save your jungler and turn the table around and win an early kill while saving a fight.
2)When you want to finish a low life oppenent trying to back or play safe
3) When you need a 100% reliable charm (the flashed charm cancel the animation, so it makes really difficult to dodge)
4) To start a teamfight when their carry is in range for the charm+flash or R+Charm+flash
@ supuropnub For me I have been playing ahri since i got league. What you see in videos is that when pros Charm first then flash to either get that kill or confuse the enemy. For an example, When an ahri charms, she can flash to a bush or over a wall. The enemy will either use there flash or leave if low. To me its a trick to get the enemy to waste there flash so it will give ahri an advantage coz her ult can do three mini flashes at anytime. Using Q/W while ulting will make ahri a high predator/ a hard hit.
I never saw that before but I did try doing flash e or flash charm, not charm flash since there is a chance of missing with flash charm or charming then flashing may be better just in case you miss the flash.
1) You want to cover a large distance rapidly. The best example I have is the fight for the crab in the river at lvl 3. You can save your jungler and turn the table around and win an early kill while saving a fight.
2)When you want to finish a low life oppenent trying to back or play safe
3) When you need a 100% reliable charm (the flashed charm cancel the animation, so it makes really difficult to dodge)
4) To start a teamfight when their carry is in range for the charm+flash or R+Charm+flash