-Great roameing abilities
-Slow base movement speed
Wondering who the hell this guy is? Yes? Let me show you this awesome but weird hero. Rhasta is not a hero people play a lot. He was in rank 75 out of 102 for the most played hero in the 6.78 patch. Since the 6.79 patch is out, he's sitting at rank 69. He got a nice little buff with a 2 wards bonus and a new placement structure on his Mass Serpent Ward skill. Shadow Shaman is known for his great disabling and pushing abilities. He should not be known as a "support". The only support you should be giving is helping with denies, disables and wards. If you play your role perfectly, your team should be able to win this in no time. Thanks for checking out this build! :)
Like almost every hero, your goal here is to get gold and experience. Go to your lane (preferably safe lane or mid). With the starting items purchased, you should be able to stay in lane long enough. Stay in lane, get last hits, level up, harass your enemies (thanks to the range). Get your ground boots, your Magic Wand and your Bracer (rush Bottle if you play mid).
This is where you start being annoying. At this point, you probably pushed one tower in your lane and got a few kills/assists...and maybe a few deaths as well. Pressuring the enemy at this point is crucial. As soon as you get your Boots of Travel, start roaming and ganking moving as fast as lightning. Get a Bottle and wards so you can get total rune control to help you ganking. Use the Hex and the Bind to disable the enemies while your team bashes on them. If you you're not quite sure they are going to die, nuke them with your Ether Shock. You should only use your ultimate for pushing towers or team fights. Try to stay as far as possible because you can die easily. You should complete the Aghanims Scepter and the Drums of Endurance really fast.
Some think you start peaking off? Show them they are wrong! You still have two huge disables and a pushing machine ultimate. Taking barracks should not be a problem if your team knows what he is doing. If you think two disables is not enough, get Eul's Scepter, Scythe of Wyse, Orchid Malevolence, Rod of Atos, the options are unlimited! You want to troll **** out? No problem! Get Dagon, Necronomicon, Ghost Scepter or Refresher.