I have worked on this build since Leona was released and found it to be the best method of playing her.

Leona can be a great tank, initator and disabler as well as assist the team in doing great damage during teamfights with her passive ability.

This build is designed for maximum farmage, tankage and initiating. Making her a great tank to bring to any normal or ranked games.

Greater Mark of Magic Penetration - Just to counter any inital MR early game.

Greater Seal of Health - Lenoa already gets great resists from items and her shield, more HP is the way to go.

Greater Glyph of Cooldown Reduction - Her ability CDs are massive, this is to help during the time you have zero CD reduction items.

Greater Quintessence of Movement Speed - Leonas base speed is really low, having these quints makes it bearable and be able to actualy catch anyone.

Overall I find these runes the best to play with. But overall its your choice on how you play with these. Go for what you feel more comfortable with.

Ghost - For chasing and escaping. Quite obvious but you will feel quite useless with the amount of times people escape from you because you chose a quick flash over this.

Exhaust - Good for defence and offense. Not much to say about this, but it is a great summoner spell and will help you greatly on surviving and locking down opponents.

Starting Item

Regrowth Pendant - This allows you to play offensive from the get go and with your speed quints you have no need for boots this early. You can play mass aggresive at the start and last hit or harrass your opponents, but also back off and leech XP when your low HP.

Core

Philosopher's Stone - Your mana regen is not so great at the start of the game, with this item you can spam spells indefenitly as well as gain much needed HP regen and Gp5 when you are unable too last hit.

Mobility Boots - Leona is a slow hero and is all about catching and holding the enemies, these boots allow you to roam easy and escape from ganks if your good enough.

Heart of Gold - A good item to beef up your HP early on as well as get more addition Gp5 which leads on to your main tanking item.

Choices Choices

At this point you can deviate on which items too get. If you are against a AP heavy team go for FoN if not RO.

Randuin's Omen - Brilliant item which boosts your armor massively, as well as giving you a great on use for teamfights and chases.

Force of Nature - Gives you the much needed MR aswell as tons of HP regen and more speed. An amazing item to keep you alive and chase.

The rest

Now you can either grab a QS or FH, whichever is needed the most. If you feel you are getting stunned and disabled too much or are needing more MR grab a QS, otherwise a FH too reduce your CDs and give more armor.

Frozen Heart - CD reduction, great for Leonas long Cd spells and gives tons of armor for those annoying ADs.

Quicksilver Sash - If you feel you are getting disabled too much, a much needed item to pop at the right moment. BV is also great but you have less choice of what to resist but brings you more tankage.

Shurelya's Battlesong - You more than likely wont get this far in the game to grab this, but a great on use ability for chasing, and more tankage.

Early game - Rush brush, if you are with another hero with a stun you are more than likely going to hit first blood or seriosly damage the enemy team to spook them. From here on last hit as much as possible and harass with you shield explosion when the chance shows it self. Do not be afraid to Zenith Blade a hero, stun and run. Just to keep them on there toes.

Mid game - Roam roam roam, by this time you have great mobility as well as skills to catch and hold down a enemy hero. When you see a free lane dont be afraid to jump in and Eclipse a minion wave and finish it off with last hits, you have a easy way to farm whole waves and not worry about mana, just do it.

Late game - By now you should be able to tank tons of damage as well as catch anyone you want. Look for oppurtnitys to Zenith Blade a overextending hero and deal massive damage with your passive with the help of buddys. If it goes wrong you can just pop your shield, Omens and get the hell out of there with your fast movement speed. If not, you can cause serious harm to anyone who chases you and maybe pick of a squishy.

- Eclipse takes down a whole wave to low enough HP to almost last hit them. Leonas attack speed makes it really easy to do this, beating your own wave to the kills.

- Use Zenith Blade to last hit when you are unable to get in close and personal. Just becareful not to hit an enemey hero and pull yourself into doom.

- Your ult has a MASSIVE range, you can use it at max range and the enemy will not know where the hell you came from before your on top of them with your Zenith Blade, blowing them skyhigh and stunning any runners for your team to pick off.

- Expecting a team fight in Jungle at start? Pick Eclipse first and watch your team do insane damage to theres when you explode on them all and debuffing them with your passive.

- Leona is a great hero to tower dive, pop your Eclipse, Zenith Blade in and stun your target. Tank the tower whilst your partner deals the much needed damage to finish them off and get out safely.

- Use Zenith Blade wisely, if you are getting chased and you know you will proberly die run into a brush and Blade the enemy. Ussally this casues much confusion to the enemy as they try and figure out whats happening whilst you are double backing on yourself too freedom.