I have seen modified maps that have large trees and also have things inside and pyramids with gold blocks, I would like to know if to create these maps you need to install some type of mod or only used a special seed
That would either be a mod or a world somebody created in Creative or with some editing program.
Seeds don't change the type of world, they just are used to generate the random numbers that determine where the standard parts of the world go.
(Apart from some that demonstrate a glitch in the world generation, generating worlds with continuous strips of repeating mineshafts.)
Is that I have seen it on several servers and I do not think it was created by a person and if it were a mod I would like to know what is called xD
its made by a person, normally via the mod WorldEdit (that allows you to easily edit things ingame like build spheres with a simple command
what is happening?
what what what
it seems like Sarium, the God of Chaos returned....