I got 4
1) Item management is a very significant aspect of what make the ps2 mh games unique. Lack of a farm and lack of powerful, regularly purchaseable consumables means we don't expect each other to throw all of the resources at our disposal into every single online hunt, cuz we'd just run out of mats all the time or have our boxes constantly plugged up by consumables. IMO, this makes the ps2 games so much more chill to play than later games: It makes us instinctively prioritize efficiency over absolute peak performance, and discourages us from being super critical over how other people choose to play, while still leaving us the option to use those items on the few hunts where we really need them (pitfall traps for mhg black gravs, claws for fatalis, flashbombs for mh2 kushala, etc)
2) Lack of quest-end rng charms/rust/ancient weapons is great. Charm farming is just bad content padding, and set-building is so much more fun not having to worry about theoretical but nigh-unobtainable equipment
3) Auto-guard is a wonderful armor skill. It essentially eliminates reaction speed, dodge timing, and hand dexterity from the list of skills required to successfully hunt a monster. The only drawback (beyond opportunity cost in set-building) is that it requires a pretty big playstyle adjustment to access all the benefits that it offers. If i'm still playing MH when I'm in my 70's and living with crippling arthritis, it will be thanks to this skill
4) I think dos has the best multiplayer lategame experience of any ps2 mh game, but the village experience is poorly balanced to the point of being not very fun a lot of the time
5) Dos' PvP mode is amazing and totally worth exploring and developing (not a hot take, just thought i'd throw it in
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