Hi guys. It's me, Lowan, again. This time, I introduce you with my Siege Focused build.

With this build, you can deal greatest Siege Damage, also handle most of team combats.

Btw, check out my other guides for:

Kael'thas
Johanna
Nazeebo
The Butcher

There some varieties you can select, but I recommend the build how it is as you see top.

T1
Barbed Shot: It deals double damage to non-hero characters (not structures). This provides you speed lane cleaning, also stopping enemy camps swiftly.
With the Wind: It can be an alternative when you want to take First Blood, don't missing last hit enemies and control the lane.

T2
Envenom: I don't want to explain why this is the best among its tier.

T3
Life Drain: You won't need this too much but it will make differences while you're chasing by enemy heroes. Also effective when end of combat.
Shade Form: It's effective while you KNOW how to manage Haunting Wave, otherwise it's not that useful.

T4
Wailing Arrow: It's effective in matches which based on team fight.
Possession: It's effective when enemy team has more forts. Use this ULT carefully, mostly for big damagers or catapults.

T5
Overwhelming Affliction: It provides %5 to %25 slow effect with basic attacks on heroes which you're chasing. Good.
Evasive Fire: It provides %10 to %30 movement speed when shooting with Withering Fire, good alternative for chasing or running back.

NOTE: %30 > %25 but OA debuff affects enemy which means all team can use the benefit while EF buff is only self, which means you have to use it properly.

T6
Blood for Blood: This is not neccessarily but I recommending it for survive. I'm using it to enemy with lowest life in team combat to get easy kill and gain some health in the same time.
Cold Embrace: Provides vulnerability, which helps to deal better damage to tough heroes such as most of the warriors.

T7
Deafening Blast: It provides %50 MORE DAMAGE & twice long SILENCE! PERF!
Dark Lady's Call: It provides %30 more health and damage bonus to your possessed servant AND ALSO you can possess ENEMY MERCENARIES when they send them to your base.

As you can see, talents are mostly situational. You have to understand how the match goes and you have to foresee what you will be needed.

Spam Withering Fire to:

Clear minions quickly
Chasing and harrassing enemies
Taking forts

Use Shadow Dagger when:

You lost a little amount of health
If you're going to miss an enemy with lowest health (make sure that will be the last hit)
Taking forts to sleep them
In team fight to get some health and give some chain damage

Also, don't forget to use Envenom and Blood for Blood, those are the biggest helpers to win fight and game.

Use Wailing Arrow to gain advantages on team fights, avoid to use when 1on1 or 1on2 or etc... Wait for at least 3 enemies, if it's not extremely needed.

Alternatively, use Possession as much as possible. It will provide NPC advantages.

Haunting Wave needs to be trained. It provides awesome combat advantages but hard to use. Because you have to stop for a second to cast it and after you cast it, you have to observe the map and area in the same time and decide to use it for teleport or not. If you learn how to use this skill properly, you can bring huge victories.