Level 20 is max level of GW.
Basicly, there is no uber armor. All the armor for every class has the same stats (well, armorvalue anyway), you can throw runes on the armorpieces (one on each piece) that give anything from +1 to +3 in a certain attribute class (same as a talent tree in WoW). In the end, every player has the exact same armor statwise (they only differ in looks, from crap to ubaromgwtfpwnlooks) with runes that apply to their attributes (talents).
This gives GW a a PvP-gameplay that is purely and 100% based on tactics and skill. WoW PvP has a lot to learn if Blizzard wants to give players a fair and skilled PvP experience, but then again, WoW is a PvE game, so I'm not really surprised that they keep it this way.
I'll give you an example of how armor and attributes work in GW:
Let's say you're a Ranger, you get the 4 attribute classes of a Ranger:
- Wilderness Survival
- Marksmanship
- Beast Mastery
- Expertise
You can go on and spend points in those attribute classes. The more points in 1 class, the more effective the skills that uses that attribute.
For example, Marksmanship applies to all the ranged attacks for a Ranger, so if you go and spend points to max out Marksmanship (13 points), a skill like "Power Shot" will add +34 damage to normal damage, if you don't spend any points in Marksmanship, this skill will only do +10 damage.
Expertise, on the other hand, reduces the energy (mana) cost of all your skills. And so on and on.
The task of this ranger now, is to find a perfect balance for PvP purpose, since he can only take 8 skills with him to combat. So a Ranger can either go pew pew versus certain professions (other name for classes in WoW), or find mixture that allows him to be as effective as possible to most other professions. This alone is a huge part of the tactical side of GW.
Anyway, about the armor now. There are 3 types of armor: cloth, leather and plate. Ofcourse, Plate will have the most armorvalue and cloth will have the least. But every level 20 plate armor will have the same amount of armor, same goes for cloth and leather.
Now, when you buy your armor, you get the basic armorpieces for your profession (duh), meaning that it'll have the armorvalue and stats like +xx energy and resistances for magic/piercing attacks. When you have bought your armor, you can go and slap runes on them that give +1, +2 or +3 to a certain attribute class (leaving you with a maximum of 16 points in an attrivute class (13 + 3). You can slap only one rune on each armor piece, and they don't stack (so you can't have like 5 +3 runes of the same attributeclass), there are also runes that give + health to fill an empty space.
In the end you just get balanced PvP because no player has uber gear and everything comes down to knowledge, skill and tactics.
Oh, and you can also get a second profession, so you have like a Ranger/Monk, so you'll have the attributes of the Ranger AND the attributes of a Monk to spend points in. But you won't get the main attribute of the secondary profession (in this case, Monk), thus the monk attributes will be less powerful/effective (main attributes being attributes that affect the 3 other attribute classes of a profession)
PS: I play and love both games
