Leona is a highly aggressive engage champ. Ideally you have an ADC who can follow through and burst damage as you lock down the opponent and stack them kills. When in range, her E->Q combo is great, and if they are out of range of your E, you can ult them if you can follow through with your E->Q combo. Stun them into submission and carry your lane to victory. Leona's kit has great engage potential, as well as peeling capabilities.

Hey guys, Lufifmrrrrr here! I have been playing League casually in the Gold division for the past several seasons. Mostly play with friends to have fun, but have been getting into ranked games more seriously recently. I main support, with Leona making up the majority of my gameplay. I also try to stream a game a day - Lunch with Leona - for the fans (which are a handful of my own friends).

PROS:
Tanky
High CC/Peel capability
Gap Closer (with her E and R)

CONS:
No Poke
Minimal Damage
Single Target lockdown (besides her R, which can snag a group)

(Work in Progress)
Resolve is your bread and butter - it synergizes with your w perfectly.


Secondary Runes:
I see lots of Precision and Domination runes, which are situational in my opinion. Some for CC break, anti-poke, but A real lane sustain option which I feel happens the most when you pick a Leona, is the biscuit delivery and Cosmic Insight which gives you CD on your Locket and Ignite.
Another option is to go hexflash for aggressive lanes for when Flash is on CD. I am not a huge fan, but it is an option if you use it a lot.
I used to go magical footwear, but the minimal movement speed increase isn't worth it compared to the CDR on the ignite/locket.

Locket is a go-to, it gives you a shield that you don't have in your kit already. Sunfire is a good tank/damage item, but you are Leona and are very tanky anyways. In my math history, I go Locket 95-99% of the time, with Sunfire VERY sparingly.

The rest of your build depends on if you want to be a full tank (as in you don't have any other in your team) or if you can peel and be a support Leona. The two builds differ greatly, as Dead Mans Plate/Force of Nature will help you, while Zeke's/Knights Vow help your carry. You need to identify what your team will require, which can be done at champ select, or as the game moves along.

I like the attack damage for longer fights over the Bulwark. In general, the Bulwark will provide the burst damage from your shield break, but if you are auto attacking well, then Pauldrons will be better. I have looked at both damage output and they are similar, the difference is when that damage comes.

I love this item on Leona. Think of this scenario - you are running back to lane and the enemy team is pounding on your turret. You get there quickly and have Momentum built up. You ult them in range, E to close the gap, auto them with Momentum, Q stun, auto again, and by this time your ADC is there finishing them off. Beautiful.

This goes along with the movement speed option, which is good for catching up for a Q stun, or closing gaps faster. This, Abyssal Mask, or Spirit Visage are good options. Check team comp and make your best decision.

Great support item to help your ADC burst more, and the item gives ability haste to help you stun more often, and mana for longer fights. A must have. Love this on Leona.

Another support item, redirecting damage from them to you, helps survivability of your ADC. If you already have a tank on your team, this is a great itemization option with Zeke's.

Leona doesn't have a heal, so this rounds that out, especially with the Locket. If your team doesn't have a lot of heal/shield capabilities, then this is an option. Not my first option, but has its place in some games, and could be taken over Knight's Vow.

Obvious tank item, anti AD, anti heal. Grievous wounds if they have a lot of healers (Renekton, Aatrox, Mundo,etc.) Would take this over Dead Mans Plate.

Use this is you are the only tank on your team. This will make your W shield a little better and give you some more health regen so you can get back in the fight if it lasts long after your engage.

This item finished out the Tank Leona build. If you are the only tank, this over Zeke's might be required, and if your game lasts 35+ minutes where you have enough gold to be full build.

Not my favorite item, could be taken over Warmog's depending on team comp. If they have true damage, you need the health, if they are all melee, take this.

This will increase the damage done on your stunned targets. Real good for teamfights and increasing your teams burst ability. If you need more burst, take this over Force of Nature.

Final item here, if the game is lasting a long time, you have a good team comp, and you need wards because its still a close game taking place in the jungle. Wards Wins Games.

So as a visual aid baseline;
Every Leona needs this,
Then, if support and not the only tank, pick these two:
If enemy team AD heavy, pick an Armor item from here:
If AP heavy, pick an MR item:

Depending on champ select, you may have the best level 2 all in and be able to get a kill early, or at least summoner spells. For example, if you are bot lane with Leona and Lucian, you have THE BEST level 2 power spike. I don't care who you are playing against, you can go in with E->Q, Lucian can follow up, and they will die so fast they might ff right then and there.

However, not every game goes that way. In the early game, it is your job to find and execute picks on their laners. For example, if you see their support running off to ward tri-bush, that's a signal to go all in on the lone ADC, assuming they don't back off.

Early game really only goes 2 ways for Leona. Either you are being the front line bully because they don't have poke, or you are getting pushed into your tower because of their mage support duo poke lane. If you are pushing their tower, getting a pick is harder as you don't want to tower dive. This is fine, just wait it out and hope your ADC is farming better than theirs, and watch for the jungle since you will be on their tower. If you are getting pushed, then wait for your own jungle, try to make a pick if they ward, and don't spend all early game getting poked down. Let them push and call for help - THIS IS A TEAM GAME!!!

This is where things get interesting and can take on all sorts of forms. If you are winning lane and you have an ADC that can handle themselves, i.e. Trist, then you can feel free to roam up to mid lane and gank or pressure with them. Get some deep wards in their jungle to make sure your solo ADC can see when trouble is afoot. I can't stress this enough - WARD, WARD, WARD MORE. You should always have 2 or 3 wards out plus your control ward. Vision wins games.

This part of the game you really need to determine what your role is in the team fights. Are you the only tank? Do you have several bruisers? Do they have all-in dive characters? The thing about Leona, is you have such a great engage, you are always pinged to engage first. But keep in mind you have to peel for your carry too. If you have someone else engage, follow through and try to get several people in your ult stun. You can be front line, and then E back to your carry to peel for them if the enemy team dives. The biggest thing is to be a presence in the fight. That might mean using your entire kit on a single enemy player (see a fed Renekton), or using your stuns on multiple players (see ulting a ranged MF, while Q stunning the opposing Kat ulting your entire team. You need to see everything that is going on, and act on it clearly but calmly. Take a deep breath and slow things down before a major teamfight. Missing some stuns or not peeling correctly can be the difference between a win and a loss.