pros
-good suport character/color]
-can stun like a cow
-heavey armor and magic resistance
-very tankey

cons
-runs out of mana very fast in the beging
-can not 1v1
-gets destroyed by otherr tanks
-hard transition because she deals almost no damage

over all leona is a very good champion. Do not listin to other players that think she is over power she trealy is not op she prbly maby be getting a but sometime in the up comeing patches. make sure to use her stuns as much as you can because they are life saves

Leona is a suportive tank her Solar Flare and Shield of Daybreak are very good stuns together. her Eclipse provieds lots of survive ability. Zenith Blade is good for a quick enter and stun. it is also good to pick up a running enemy and either kill or stun and team kills.Leona is not damage at all she is not played ap for any reason
cool down reduction is her best freind but she is a slow champion

flash: always get flash is a great spell for escaping and lineing up for skill shots or just cating up to a person
heal: just in case you are gonna die or a friend is gonna die heal is a betch that will be your Friend

this build is almost all armor and HP regeneration magic resist runes are a must for her
if you want this to be changed you can make flat health quintessences and put some armor runes in there somewhere they work well but if you aren't sure about those runes go for those

masteries Leona is ALL tank her damage is terrible but her support is amazing so build on that good thing and making sure u get the ultiment it goes great with all tanks
and the hp rengen, armor , magic resistance is always a good thing to have dodge is not that geath with leona you would rather have it in you cool downs reductions some people go utility with her but that is a bad idea she already has enough cool down reduction with her items so you dont need anymore you should focus on the armor and survivability with leona

kindle game: provides early CD reduction and good health
merc reads: they are the best
Frozen Heart: good item for leona , armor, mana, and cd reduction
shurelya's reverie: good hp regen and item use it can give ur team a bost of MS to get that teemo
warmogs: health for tanking and regen
magic resist: magic resist, movement speed, and more hp regen!!!!
arch angels: you will be focused because at lvl 18 ur stun will be 3-4 sec ur ulti around 40 sec and eclpise will always be active

why cd reduction and hp regeneration
hp regeneration is amazing your going to get hit hard hp is good but if you are booming out 100 hp every 2 seconds you can tank with 2000 hp and your skills are ur life
you can stun every few seconeds to make sure they never get away good for countering there carry and ultiment is 40 sec cool down so u can use it to enter and use it a few seconeds after exiting
it is a pretty balanced build i seem to do good with this you can switch items if you arn't doing so well hold off on the shurelya's reverie and go right for warmogs if you are dieing faster then you want to be

EARLY GAME: Get a ruby crystal for hp. all you have to do when you start to lane is gank the other team when ur partner wants to for harassment!!!
comos
eclpise
zenith blade
shield of daybreak
then run to ur minons OR get the kill if u are laneing with the carry

if you are laneing with another support use you shield of day breaK to keep alive and use you eclipse to last hit lots of minons you can use you zenith balde to kill minons but you might hit an enemy champion and be in a horrible position

when you team fight u want to be the first one in there. useing the ulti in a team fight is difficult
only use ultiment when the are bunched AND you know it has started dont use ultiment when you run in and no one follows
try to stun the damage most of all to ensure that your team will survive a little be longer
and if they depend on 1 or 2 over fed champions to most of the work stun them and the Ultiment and stun again to take them out of the fight
THE MAIN THING IN ANY TEAM FIGHT
don't be greeddy
Example: a 200 hp temoo running away or a almost dead teammate getting hammerd by 1 more
please please please!!! help that teammate Leona is ment for support not kills

OK well first allways use bclpise vefore you enter it gives great defense with an explosion at the end
after that zenith blade you temas target (carry)
use Shield of Daybreak
now if they have alot of health still let off if they are half health Solar Flare then Shield of Daybreak

(leons best place to use there ulti is on the line of they skill its perfect if they are really slow let them get inward abit)