whenever a new game from MHF series comes out, its hard to get good weapons fast. I always looks it like this:
1. Khezu is always easy to me using short swords, so after i defeat a lot of them, i can forge thunder type khezu weapons.
2. After i hvae thunder type weapons, i go to quests where monsters are afraid of thunder, like plesioth. Then the path to water type weapons are open to u.
3. After i obtained water type weapons, i go to quests where monsters are afraid of water, takd gravios for example. Then i can create fire type weapons.
For dragon type weapons, i farm lao shan lung, pretty easy but takes a long time