Once you leave the starting area of Hokolo Island in Monster Hunter Stories 2: Wings of Ruin, you'll start encountering Royal Monsters in some locations. These tough monsters will allow you an early chance to get some monster materials that usually don't show up until later in the game, as long as you can defeat them that is.
Navirou will warn you whenever you get close to a Royal Monster, so you can prepare yourself accordingly (or avoid it to live to fight another day). These monsters are sleeping and will not attack unless you run directly into them. We have a full list of each Royal Monster right here, as well as where you can find it.
We haven't had any luck in making Royal Monsters retreat from battle in order to spawn an egg den, so it could be that this isn't possible with them. However, we've still included the method that increases each monster's retreat rate in the table below in case we have just been unlucky.
Tigrex
Monster
Location
Retreats?
Hatchable?
Weakness
Loot & Parts
Tigrex
Alcala (left map)
Harzgai Rocky Hill (right map)
Yes (Break the head with a sword after it steps on a shock trap)
Yes
Head: Slashing
Legs: All
Tigrex Scale (1 pt)
Tigrex Claw (3 pts)
Wyvern Stone (1 pt)
Tigrex Scalp (10 pts)
Monster Bone L (10 pts)
Break Head: Tigrex Scale (1 pt)
Break Legs: Tigrex Scale (1 pt)
Monoblos
Monster
Location
Retreats?
Hatchable?
Weakness
Loot & Parts
Monoblos
Harzgai Rocky Hill
Yes (Defeat it using a sword and shield when it is paralyzed)
Yes
Horn: Piercing
Stomach: Slashing/ Piercing
Legs: Piercing
Tail: Piercing
Monoblos Shell (1 pt)
Monoblos Ridge (3 pts)
Wyvern Stone (1 pt)
Blood Red Horn (10 pts)
Monster Bone L (10 pts)
Break Horn: Blood Red Horn (10 pts)
Break Stomach: Monoblos Shell (1 pt)
Break Legs: Monoblos Shell (1 pt)
Break Tail: Monoblos Shell (1 pt)
Gammoth
Monster
Location
Retreats?
Hatchable?
Weakness
Loot & Parts
Gammoth
Loloska
Yes (Defeat with a Glavenus Kinship Skill)
Yes
Blunt
Head: Blunt
Nose: Slashing
Tail: Slashing
Legs: Blunt
Body: Blunt
Gammoth Hide (1 pt)
Gammoth Shell (3 pts)
Gammoth Tusk (10 pts)
Fortune Fang
Break Head: Gammoth Hide (1 pt)
Break Nose: Gammoth Hide (1 pt)
Break Tail: Gammoth Hide (1 pt)
Break Legs: Gammoth Hide (1 pt)
Break Body: Gammoth Hide (1 pt)
Zinogre
Monster
Location
Retreats?
Hatchable?
Weakness
Loot & Parts
Zinogre
Loloska
Yes (Defeat with ice element attack while it affected with Blastblight)
Yes
Head: Piercing
Body: Piercing
Tail: Slashing
Zinogre Shell (1 pt)
Electro Sac (1 pt)
Zinogre Shockfur (3 pts)
Zinogre Plate (10 pts)
Fortune Fang
Break Head: Zinogre Shell (1 pt)
Break Body: Zinogre Shell (1 pt)
Break Tail: Zinogre Shell (1 pt)
Brute Tigrex
Monster
Location
Retreats?
Hatchable?
Weakness
Loot & Parts
Brute Tigrex
Lamure
Yes (Break the head with a sword and shield after it steps on a Shock Trap)