DMCV finna take the crown in a bit
Really surprised with the lack of Mon Hun in this thread.
I really wanted to say MH World for best, but I think monster fight design is worse in world than Gen 3/4. Monster fight design has always been what sets monster hunter apart. Sure the weapon movesets are fairly diverse, but if you compare any 1 weapon to something like a weapon in Nioh or a character action game like Bayo or DMC then you can see that your options are much more limited. This leaves the monster fight to carry the weight. You can tell how each monster fight was carefully crafted to have the perfect openings for each weapon to punish the monster's attacks. Watching a GS or hammer user completely dominate a monster by perfectly predicting the monster's movements. Influencing monster behavior by standing in a certain spot after a certain move in order to set up a punish 10 seconds in the future. This to me is what made monster hunter special.
Something changed in MH World. Monsters no longer have these predictable patterns and (more importantly) many of the ways players could influence monster patterns are gone. The number instances where you can bait a monster into a certain pattern are extremely small compared to previous games. Monster design seems to have been done with little thought put into how the weapons would play against them. I'll use deviljho as an example in world. In previous games using charge blade, there were a number of attacks you could exploit using a guard point > AED. Stomps, breaths, hip checks, etc. The recovery time of the monster after these moves left just enough time to get this attack off on a weak spot. Now in world, all of these openings are too short to do this move. So what options does the player have to punish attacks, well they just do the attack anyway and pray that deviljho just lingers in the spot just long enough to land the attack. It's no longer knowing exactly what you can do in after x attack to do maximum damage while remaining safe and ready for the next attack. Now it's OK just throw out the attack and pray it hits because the truly safe openings for this attack are so few that if you wait for them you will just be wasting time. It's now better and faster to just throw out the attack and get lucky. Sometimes you will miss and eat shit for it, but if you compare your clear times with an optimized run but using the safe approach, you will be much faster just throwing out your super moves and hope they hit. This was almost never the case in previous games. It's like the devs forgot to design the monster FOR the weapons. I won't get into the god awful maps here, but again it seems like a similar case where they forgot to design the maps FOR the weapons.
This is speculation on my part, but I think this is the reason that Greatsword plays nothing like it did in previous titles. This weapon more than any other relied on prediction and influencing monster patterns. When they took that away, they took away the weapon's core and it needed a redesign.
Anyway, sorry for the ramble, but this felt like a decent enough place to post my thoughts on MHWorld's combat.
So while the movesets for weapons are more fluid and interesting on average, I think that the game has lost an important part of what I think of when I think of monster hunter's combat.