Get both if you can. Otherwise, GW: Prophecies is the original campaign. GW: Factions is kind of an expansion but you don't need the original to play it. "Prophecies" has more content overall, so if you're only getting one, it should probably be that.
I say get the new one "factions" becuase its got all the new stuff and new classes and armor and skills. They added newer pvp stuff. so i suggest factions. but remember factions and the original versions are two totally different styles. factions alow you to level really quick and drop alot of money for you to unlock skills but there arnt many quests ou there that let u unlock skills. on the other hand the original one is more of a grind and doesnt drop money as much as factions so its hard to make money. but they do have skill quests to unlock skills. but i still say get factions cus its newer.
I always reccomend new player buy Guild Wars before purchasing GW:F. The original has a much better learning curve and more content, it basically will allow you to get a better feel for the game.
Comments
Get both if you can. Otherwise, GW: Prophecies is the original campaign. GW: Factions is kind of an expansion but you don't need the original to play it. "Prophecies" has more content overall, so if you're only getting one, it should probably be that.
The Obsidian Kings
suggest Factions, simply because there's more people playing it.