Pet classes have long been heralded as excellent solo classes across games
Not All Classes Are Created Equal: I stand by my long time stance that all classes can solo. I will concede though that some Shaiya Gold will do it better than others and some require a much steeper learning curve. So how do you know which classes make the best soloers?
Be the Lone Hero! Word on the street is that the Guardian has a survivability that can be quite impressive. If you take the Guardian's natural ability to take a hit and spec your feats for damage, you have the potential to burn through mobs and come out fairly unscathed.
Many find soloing be very different than grouping, but there are some basic elements that when grasped can make soloing not only possible, but very effective! These elements not only apply to Age of Conan specifically, but many will be applicable regardless of which MMOG you choose to play.
Another good solo class is the Necromancer. Pet classes have long been heralded as excellent solo classes across games and it continues to hold true in Age of Conan.
It's a difficult class to get the hang of in the lower levels, but once you get a little higher up there you should do okay.