Before we start note I said "BEST" not "most fun". Last wish and Kings Fall have a few things in common that make them the best. They both have quite a good amount of encounters as well as bosses. They both have a large and visually pleasing overall map with great atmosphere. Kings Fall goes for a purely dark theme and somewhat grand scale while Last Wish goes for both a light and dark theme with grand scale. Both have a very large final boss with a pleasing death. Never in Destiny was I more pleased than when I saw Oryxs corpse floating off into space after so many attempts (and multiple days considering this was the first raid boss that took me more than the first day). Similarly Rivens death is also pleasing as we get to run down her throat and shoot the blight/heart (the running the heart section is also a nice surprise/ bonus that I've been waiting for. Sort of an escape the raid scenario) Both have mechanics that require a lot of teamwork but are definitely not overly complicated. And they also require a bit of mobility and moving around the map which is much better than just standing in tiny spots damaging bosses. The main argument I saw against both of these two raids was that they took too long and had annoying mechanics that were complicated to coordinate (another reason some people complained they didn't like Leviathan). I disagree wholeheartedly with these people. Maybe it took a week or so to teach people but if you had patience people have now developed great numbering systems for every encounter. Finally I would just like to say that so many people call Wrath of The Machine or VoG the best raid... why? I can maybe see how they're more fun in some ways. And I know the Destiny community loves to rush through getting loot but I mean come on... Wrath was beaten in what like 2 hours maybe or something? The hard mode world first was like under an hour? The final boss was great sure. and some other sections were fun and fresh too, but it doesn't truly challenge you or even get you in the raid atmosphere. It feels like a constant speed run. And let's be honest by today's standards VoG is a cakewalk. Consider atheons mechanics... they're a joke... teleport and shoot oracles then damage... if that released today with all our experience, even if we had to guess, and even if we were underpowered, we would have had worlds first teams done in the blink of an eye. We've grown as a community with challenges so they needed to make the encounters do the same to keep up. It's that simple.