Awesome! Killing all those monsters: from the tiniest hornetaur to the most epic white fatalis! It's just great.
You start as little nobody-hunter, in your village. Soon you get the first rewards from monster that you kill, from ore picking and from collecting a huge amount of other stuff. Then it gets more and more addictive. With the stuff you collect, you begin to create new equipment: new armors, new weapons and other essential things for a legendary hunter.
The best thing of the game is definitely the multiplayer. Hunting a Rathalos with your hunting-mates is just... well, there aren't words to describe what you feel by taking down one of the wyverns with your own strategy.
The only thing you must be aware off is: when you enter this world you will never come back.