Finders then receive an official certificate and a display stand for their egg, and can take their ... the Standley Monster will continue to lay eggs — and take rainbow poos — through the ...

This is basically the only way to get Rainbow Rarity eggs from Royal Monster Dens. You can use this method on any Monster Den — retreating monster dens will also (very rarely) spawn Rainbow Eggs ...

Another step is to research 15 monsters to level 6. The third task before you can unlock the rainbow pigment in Monster Hunter World is to research 15 monsters enough in order to make their ...