Here’s the Kinetic class you can eventually spec into from the 3 beginning classes. You have to earn “sparks” from quests, dungeons and other objectives in order to start moving through the nodes in the ascension atlas and get the class you want. If you do not know what the ascension atlas is this will help to clear things up: http://sf.my.com/us/news/announcements/ascension-atlas
You can get any other information about skyforge there as well.
The other classes are on my Youtube channel.