Spirit Breaker + Lifestealer

I was playing matches with some friends yesterday when we found about a really fun and effective strategy for Spirit Breaker and Lifestealer.

Spirit Breaker starts in the short lane(next to the jungle) while Lifestealer jungles to level 6.

Once both get to level 6 they can become a gank bus. Lifestealer uses his Infest and gets inside of Spirit Breaker. Spirit Breaker then uses his Charge of Darkness to charge anywhere on the map and hit an enemy hero. Once Spirit Breaker makes contact Lifestealer jumps out and hits them for ~400 damage. Spirit Breaker then uses his Nether Strike to stun the hero some more and between the two of them most heroes will be squished.

We started having trouble with this when the teams started roaming together. The gank bus does not work very well against more than two heroes.