Been listening to the shaka session from 1978 at Club Noreik. At around 24 mins he plays the most fyah tune and if anyone has the session handy would love to know who does it. Can't seem to upload it from itunes to the thread.
The year of the tape in question (1978) should provide a clue that the tune is not Little Jimmy/Serious Warrior which Shaka first started playing around 1986/87. As Simeon stated it's simply called Warrior and nobody knows who the vocal is by but what can be said for sure is it's one of a batch of killer Sly & Robbie dubs which were played by a handful of sounds but made famous by Shaka. Dating from around 1978 they included Rocks & Mountains plus Jimmy Riley's We Are Not Free, none of which were ever released until the recent Digikiller release of Rocks & Mountains. And finally, the Meditative Sounds cut posted by Imp Sound is a recut, not the original.