PVE-sets focus on doing more damage without getting hit yourself, PVP-sets focus on staying alive and being able to take damage by having more stamina and resilience. Obviously in PVP: pvp-set > pve-set.

Arena sets from the current season (season3) are best of all. You need arena points to buy these. With the arena points you can also buy the arena sets of season2 for a reduced price, those are less good of course, but less costly. You can use bg purchased and arena purchased items everywhere. 

Gladiator set is the arena season1 set which you can buy with honorpoints, get those and replace them with newly purchased season3 items from arena later. The Vindicator items are the season3 bg-items which u buy with honorpoints. They are no set, just separate items that fill up the spots that your arena gear wont cover (bracers, belt, feet, necklace, ring). Get those.

The veteran items were the season2 bg-items, but you cant buy those anymore, except the ring which u can put in the second ring slot (first ring slot will be vindicator ring).

In short, get all vindicator items and season1 set with honorpoints. Replace season1 set with season3 set through arenapoints. Also try to aim for about 400 resilience with your gear+gems+enchants.

PS the real 'noobs' are the people who have questions about the game but dont ask or look for answers.

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