To get a royal ludroth egg, you will need to progress to the Alcala region in the game, which is the second game area. However, you will need to look inside monster dens, but you should first try finding a royal ludroth. You can find ludroths usually near water sources and inside monster dens at times, including everdens.
In our game, we found a royal ludroth in the everden that spawns in Alcala Highlands. You can find this everden in the location shown by the map image below, and inside this den, you can potentially find a ludroth. When you find the ludroth, start a combat encounter and force it to retreat.
Forcing monsters to retreat will, in turn, guarantee an egg drop for that monster, and you can increase the chances of a monster of retreating by wiping a paint bomb at them or breaking all of its parts.
That being said, you can break all of a Ludroth's monster parts by using both blunt and range damage from both a hammer and bow on the head and bladed weapons on its body. Using both weapon types combined with a paint bomb, which you can get from paint bomb, will increase retreat chance.
You can also try throwing the paint bomb at the Ludroth when it has low health for the best results. However, this will be tricky to do if it's your first time encountering the monster, which in that case, we would recommend doing it a few minutes into the fight.
Once you beaten and forced the ludroth to retreat, a monster den labeled ludroth monster den, will appear close by. Inside this monster den, you can find a royal ludroth egg, and it will look like the one above called a soggy leviathan egg.
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