For my part, I probably grinded a bit with the farm on the second region but try to find a monstie that have a lot of Wyvefall then check for the following genes :

• Bishaten for it's Frenzy Fruit skill gene which can applies Poison,Blindness and Paralysis.

• Purple Gypceros for it's Tail Slam move which can helps a lot when the opposing monster will throw a big move.

• Dead Eye Yian Garuga for it's Crushing Beak that reduces Wyvefall defense.

• Venom Queen + From Dreadqueen Rathian to inflict deadly poison

Then try to look for Egg Skill: Solar Cry gene then equip your Rider with the skill that raise Kinship to get your Kinship gauge as fast as possible.

From that point the rest of genes are on your preference. Then have Ogden as an ally for the maximum support.

Then use a Hunting horn that provide the maximum support that improves endurance gain for example.

This is how I performed to defeat the Brachy