I dont got time to fix this whole build at once.

Hey and welcome to my description of Brand.
I checked up a few builds before i tried Brand the first time, but all builds lacked HP and early DMG. So i made this one.
Check it out, this is how i play Brand.


Pros
Superb Damage
Passive Damage Over Time
Massiva Area Of Effect capanilitys
Great Farmer

Cons
Poor mana pool early/midgame.
No good escape ability (except stunn combo, but that rairly works as an escapetool)
Vulnerable By CC's

I go with the same runebuild on all my AP characters to be honest.
I feel that mixing Ability Power with Magic Penitration gives you a big advantage early game,
and gives you the possibility to build other items than DMG.

Instead of buying ampifying tomb at once you can buy a Doran's ring for example, to get more hp, mana reg, than just more AP***

With that said, i go with;
Magic penetration Marks
Ability Power Seals
Ability Power Glyphs
Ability Power Quintessences


( Lets say you play Nidalee. With these runes you will be able to heal much earlygame thanks to the AP bonus, and also do lots of DMG with Spear thanks to the MP, and thats awesome )

For masteries i go with a standard 9/0/21.
Placing points in the defense tree seems pretty useless in my opinion.
You are about to play as a caster, with is a ranged character. You dont need to specc armor and magic ress becasue you are going to stay in the back of teamfights all the time to avoid being hit in the first place.

So, i go standard 9 in the offence tree, 0 in defense and 21 in utility.

When i play Brand i use Flash and Clarity for summoner spells.
So i upgrade them in the mastery section.
Put 1 point in Insight for clarity boost
and 1 point in Blink of an Eye for lower CD on your Flash ability.

Like i mentioned above, i use Improved Flash and Clarity for summoner spells.
Why do i choose these?

With Flash i can escape fast if i get focused in a teamfight or while farming.
I can also use it to chase down enemies or suprise them by flashing through a wall and begin a gank.

I choose Clarity because i dont focus on any mana reg item in my build, untill mid/late game. this makes you have a mana pool of about 750, before buying archangel staff. This is why you need clarity.