Do you need it? No.
Do you want it enough to pay for it? That’s the real question here.
For any game mode, there’s the new class, the Revenant. It’s an interesting class, but the design isn’t as solid as any of the base 8. It’s also unable to use racial skills, which may or may not impact your enjoyment of it.
Second is the elite specialization for each class. Again, these can be used in any game mode, but they are unlocked automatically in PvP only. In WvW and PvE, you have to earn them, and some people find it less than enjoyable. Some people seem to feel that they’re a “must have” for PvP, however.
Third is masteries. These are used in PvE only, including Fractals. They come in two sets: Central Tyria, and HoT. The Central Tyria masteries you can slowly unlock by playing your level 80 characters anywhere in the base game zones, and they can be useful but hardly needed. The HoT masteries are better covered in my next point.
HoT itself gives us four new zones, and they’re the most complex zones in the game by far. This is both good and bad, depending on how well you can mentally map out the more confusing areas. The HoT masteries contain abilities you NEED to make it through these maps, such as gliding and using “bouncing mushrooms”. Those masteries can only be leveled up in the HoT zones, and the fights there are much harder than those in central Tyria. It’s tough to impossible (depending on your build and skills) to play through the area alone for normal encounters, and each of the four maps has a zone wide meta-event that requires most people in the map to work together to win. Some people love it, some hate it. It’s also worth noting that a PvE player MUST play in these zones some to get enough skill/hero points to unlock an elite specialization entirely.
HoT also contains a raid, with a “not actually a promise” promise of more to come. It’s located in a HoT zone, so you need HoT to even consider getting into it. Good builds and great gear are also needed, which is a problem for some.
Finally, there’s the HoT story. Again, this is in the HoT zones, and everything I said about them applies here as well. If you simply follow the story, you will at 3 points be stopped and told to level a specific mastery to continue. If you’re really interested in the story, however, I’d delay HoT and get all of Season 2 purchased and played first. Otherwise, you’ll have no idea what’s going on.
