how many quest do i have to do at the chief dude to unlock the 4 star quest..

When you see the garuga in lvl 3 star in chief,there will be appear a yian garuga then finish it.

Guest is right. But He will appear in this quest called 'slay 10 vecliprey' you will find him in area 10 but it have cutsecne look likt it happened rathian and Yian kut yu became Yain Guage it's very strange monster in freedom PSP but this have new attack and use thing it's sonic bomb by he will big roar but it's fast. You have problem your ear. But you need cut his tail. When you finish quest. Try check it? No. It will replaced by rathalos. This only strange monster in your new game to clear 1 to 3 lvl called quest 'slay 10 vlecpirey'...! Yian Guaga will appear only in quest when you finish it replaced it. But he can be found in forst and hill area 10. You will unlock Quest for hunt the yian guaga but it's very hard. This is Rage of Guaga in this upgrent quest I think.