monster hunter is an action-rpg series developed by capcom in which you play as a monster hunter who hunts monsters. shocking! compared to other arpgs, monhun sets itself apart mechanically with things such as its focus on longform boss fights, an emphasis on gathering and preparation, and power increases through crafted gear in place of a traditional levelling system.
i was first introduced to the series with 4 ultimate on the 3ds which i just about instantly fell in love with, and have been working my way through previous titles slowly but surely since. its core gameplay is incredibly satisfying in a way very few games i've ever played are. plus, i also just love its world and art direction.
(i've also gone through world and rise, but admittedly these are outside my realm of interest as i think the changes to core gameplay they make just make the experience a lot less satisfying and interesting.)

monhun's core combat consists primarily of 10-30~ minute long asymmetrical man-versus beast hunts with strategic, positioning-focused combat.
players are generally weaker compared to most action games, having very deliberate and restricted movement, stamina management, and very few i-frames. lacking any flashy combo system, weapons have weighty and committal movesets that are simple with high skill ceilings. consumables are limited but can be vital, requiring careful management and mid-fight upkeep of things such as food and blade sharpness. while it doesn't really go for realism - monhun's design philosophy is honestly quite arcadey in some ways - it's got versillimitude where it counts to make the player feel out of their depth against monsters.

the monsters, naturally, are big, beefy, hard-hitting beasts of many different varieties, from typical fire-breathing dragons to electric cave leeches.
while monsters are much more mobile and have much larger attacks than the player, they are also limited in their own way, and often have limited attack options depending on where the player is in relation to them which lets you learn monsters' specific habits over the course of hunts. they also have their own stamina, and over the course of the fight can become significantly more dangerous when enraged or inversely weaker when tired out.
adding to this, certain limbs can be harder or softer and can with enough damage break, even being able to cut off tails completely - giving you a chance to carve the loose tail for materials and severely limiting the range of formerly dangerous tail attacks.because of this, your priority for where you want to mostly challenge a monster can change over the course of a fight, depending on how often an opening for a specific limb presents itself, the risk of being punished yourself, and the benefits of a part break.
there's a very satisfying flow to learning a hunt - maneuvering around their body, predicting and baiting moves, and punishing accordingly while closing the gap when necessary to keep tempo, with enough consistent damage sending the monster flailing to the ground for a massive opening.

when the deed is done - kill or capture - you return home with the spoils of your hunt and the game flows into a more relaxed state, checking in on your village's farm and going out on gathering quests to replenish your stock of items, using monster parts to make stronger weapons and armor, tuning your loadout for the next hunt, eating a hearty meal and setting off. while i feel it can be overlooked, the downtime between hunts is honestly vital to the experience in my eyes.

much as i am always a "first in release order" kinda person, and i do genuinely love monster hunter 1, it is a rough, bare, and demanding experience which could understandably turn some people off the series. which is a shame, because it fucking rules, but i digress.
4u is my personal favorite, though i am biased as my first experience with the series. 1st and 2nd gen are often meaner and like to throw you in deep and are a bit tighter on the resource management aspect. they also don't have the new weapons of 3 and 4 - the switch axe, charge blade, and insect glaive. if any of those sound appealing to you, 4u may be up your alley. tri has a wholly unique bowgun part system for rangers, and along with 3u has underwater combat. 4u also puts more emphasis on the story in its village quests, having you join a travelling caravan going from city to city while a monster-infecting virus is breaking out in the region. it's nothing fancy, but it has some fun moments.
and if it sways your decision, 1st and 2nd gen are entirely on the ps2 and psp, while 3rd and 4th are more spread out between consoles but mostly on the 3ds. while the official servers are down, all of them have custom servers at the time of writing, so online won't be a hassle.
now, they aren't exactly making new copies of these games. so, yknow, you can get them secondhand if that's your thing but otherwise Legal Acquisition Through The Internet will be your go-to if you know where to look.

happy hunting!