This build is an easy to use one that buffs wrecking ball and leave you with little to worry about other than using your basic abilities. It allows you to single out enemy heroes for your team to kill along with a taunt/silence that is very useful in team fights. You may switch out decimate for a slow rather than the taunt/silence of warlord's challenge.

The focus of this build is enhancing wrecking ball, which allows you to throw enemies around. You will want to throw enemies away from their team and into yours to ensure their death, and you can even throw them over your walls if they get close enough.

Increased range on wrecking ball means you can throw enemy heroes farther away from the rest of their team, ensuring their death.

Indomitable gives you an unstoppable cooldown that comes in very handy. Thirst for battle is also a solid choice that allows you to bloodthirst more often.

Into the fray allows you to armor up your allies for a fight along with damaging and slowing enemies, or to throw them to safety. You can also use it to troll :p

Warlord's challenge is a taunt and silence and is quite useful at preventing damage to your teammates, especially when it is combined with double up.
The slowing effect of decimate is useful in catching stragglers, but does not do as much in team fights until level 20 when you can talent it to reduce enemy damage output. Make sure to cast it on as many enemies as possible to lower its cooldown.

Double up works well to mitigate the damage you will receive during warlord's challenge.

Adding a stun to wrecking ball ensures your target's death and is a very strong choice.

Reducing the cooldown on warlord's challenge by 45 seconds, along with the extra 0.5 seconds, means you can continue to use this every 3 seconds as long as you are securing kills. This is very powerful in chaining together kills with your team.