This build works in most games.

Pros:
Mind-blowing aoe mana burn and crowd control!
Extremely high movement speed
Great self heal over time
Great scout/ganker in mid game.
Ridiculously long tornado
Very flexible playstyle late game

Cons:
Low damage per swing
Requires many levels to be effective
Long cooldowns on spells
Not proficient at controlling runes
Low MS early game and no escape until level 3
No ultimate spell at level 6


Ghost Walk now provides +10% ms with 5 wex, +20% ms with 6 wex, and +30% ms with 7 wex! This stacks well with wex orb's bonus % MS. v6.80 EMP is Invoker's best spell now!

After level 7, Invoker can scout and coordinate ganks with ghost walk! This tactic is best used in the daytime because ghost walk's 400 area slow effect may ruin your surprise or gank. Ghost walk still costs a lot of mana so think twice before using it.

With orchid, Invoker can kill most heroes 1v1 mid game; focus on enemy carry. Do not let them farm.
Ghost walk/ice wall can be used to initiate team fights too, not just tornado/emp.

For my comprehensive guide, visit: http://steamproxy.net/sharedfiles/filedetails/?id=185528211#158566