Haven't played Daggerfall or Arena, but... I dunno, for some reason I feel almost as though Morrowind is detached from the rest of the series. It really had... SOMETHING. It was dark, it was tribal, it was.... well, sometimes it was even creepy. I feel like, without fast travel in the map, no horses, and just a couple options like Silt Striders or ferries to get you places, the world felt so much bigger than in Oblivion or even Skyrim. I don't know why, but I feel like Morrowind was like a crown jewel of the series, but that's probably just because I loved the environment of Vvardenfell. Man, I need to play that game again.
Skyrim... oh goodness. Skyrim. It's.... it's just so good XD I'd just be repeating what everyone else has already said if I went on about it, but... yeah. It's also the only one I don't own on PC.
I know a lot of people dislike Oblivion, but man. I sunk so many hours into this game. The world felt smaller to me, yes, and the main storyline wasn't the best out of all the games in the series, and it definitely "felt" different than the rest of the game (a more Medieval feeling instead of Elder Scrolls Lore type feeling... IMO), but I still thoroughly enjoyed this game. I dunno XD
but honestly, I dunno. I feel like it's too hard to rank them because each of them set out in a different world (well, region of Tamriel) with vastly different environments and cultures with different goals and each of them achieved those goals, IMO. Well, you could argue that Oblivion's main story was lacking, but aside from that, I think each of them have their pros and cons but are all excellent, excellent games that stand well on their own. I can't rank them in relation to each other XD
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