Hello guys,
I'm playing in TR and I'm in gold 4. My main is support. You may not trust my guide and I respect that. But I tried to help a bit on braum after 20-30 custom game tries.

The armor and the mr runes for the much powerful Stand behind me as you can guess also Braum is a defensive anchor so he needs to stay alive. And ms is useful to mark all of the enemies in the team fights with Conclusive blows . I choosed a little hp rush for harashing a bit more withWinter's bite.

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I prefer defensive mastery for Braum. Because you gonna get lots of damage and you need to resist. In early, that mastery helped me a lot. Also you need a bit ms and cd reduction in early for harash. Actually Braum mastery look like taric mastery a bit.
Anyway I guess this is work for you.

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Marking an adc is really helpful at the beginning. So beginning with Winter's bite could scare your opponents (It should scare by the way). Enemy team gonna focus your adc as you guest. So pumping defense is more helpful than giving some dmg. So I usually upgrading Stand behind me. Unbreakable is enough until the teamfights. So I choose to uprade it in late.

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Pros
Amazing tank
With Unbreakable can protect most of the team.
You can continue to use Unbreakable while you're moving.
Early harash with Winter's bite
Marking multiple enemy with Concussive Blows and chance to stun 'em
Defense and Mr rush for someone with Stand behind me

Cons
Only Winter's Bite to attack (Expect Glacial Fissure)
Fail Unbreakable makes you & teammates defenseless
You need to practice for hitting an enemy with Winter's Bite
"Sting like a bee fly like a butterfly" This sentence probably telling how become a Braum player. (I'm not kidding. You have to be fast and you need to show what agility means.)

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Braum is a tank like combination of Taric and Leona. So you have to focus to protect your adc in early. You don't have too many skills to harash enemy adc. My opinion wait until high possibility to hit enemy. After 6 you can be a nightmare for continuous ulti characters like Lucian, Miss fortune etc. with Glacier Fissure. Braum kind a melee character and cd's are a little long at the beginning so don't waste your skills. And also weak against Morgana, Janna, Nami.

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I think Braum really high-skilled player hero. You have to learn to wait for the right moment. He got amazing escape mechanism (also you can use it to the minions to catch the enemy). If you success to play Braum, I think you gonna love him. Especially Thresh and BC players need to practice much because of the difference of the Q range. Even lulu players too. Maybe It sounds crazy or stupid to you but you will notice, you are using Q from far far away.

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