When I get a subclass do I retain all abilities from the main as well as the abilities of the subclass? And can I use them at the same time? For example, a main class that is melee subbed with a ranged class would have the advantage of strong ranged and melee attacks as well as heavy armor. Please clarify this.
there are rules for subclassing, first things first, you cannot become a overlord or warsmith, unless you are one from the very start, nuff said.
secondly, if you are of one of the elven races, then you cannot choose the other elven races classes (in short, if you are a elf, you cannot become a bladedancer, spellhowler, or any other class the dark elves get. and vice versa,)
and finally, you cannot subclass into a class that is similar to yours, so if you are say.....a treasure hunter, you cannot change into a plainswalker or abyss walker.
This link (http://www.lineage2.com/Knowledge/subclasses_2.html) will show you what you can subclass to and what you cannot, just click on your current class, and the restricted classes will be grayed out.