Make mesh in game

Is there a way to make the game make a mesh? i need to make creatures that have a genome and can mutate. the genome of the creature needs to dictate in great detail how the creature should look. genes can dictate whether or not a creature has fur, how long it is, what style it is (curly, straight, messy etc.) and what colour it is. The same with horns, a creature can have two horns on either side of it's head, it's genes can tell them how long they are and how sharp or blunt they look. the creatures will need appearance genes to determine the size, shape and style of the ears, tail and other features. There also need to be genes for height. i need to do all of this so i need to make a script of some sort that can make meshes based on weighted verticies and such, so i don't have to make thousands of meshes, is this possible? i thought mabey it could be done with python cause' i use blender 3D but i'm not sure