Monster Hunter has a huge diversity of animal species both large and small from all different categories of the animal kingdom. Thus, the bestiary is here for your use! All sizes of monsters will be presented with their information given to you. What ecology does exist in-universe will be covered for those interested in the lore of the world. And, more importantly, large monsters will have the secrets spilled on their attack patterns, temperament, weaknesses, and the areas they prefer to lurk in, as well as strategies to help you take them down.
Don't go alone! Take this bestiary with you, brave hunter.
After some images to show you the appearance of the monster (including any phase or appearance changes), you will be briefed on the areas a monster can show up in. Start, roam, and rest areas are all included for monsters who appear in the larger areas (single-area monsters like Shagaru Magala and Nakarkos are pretty obvious to figure out, since the map only has one area).
You will also be given a brief description and notable features of the monster, plus its biggest weaknesses so that you can go in prepared, and any other quirks including dysfunctional hitboxes (it is an imperfect game, after all). Finally, you'll be informed of all of the monster's attacks and breakable parts, plus the rewards you can get.
Note that rewards you get from breaks are always chance-based. Many breaks are the only way to get specific parts (most commonly: tails and horns), but just because you sever and carve the tail, and break the horns, does not mean you will get a tail or horn, even from the tail itself!