Terrain Crystals

Terrain Crystals allows  players to construct large spike-shaped islands out of several vanilla biomes. Crystals can convert current biomes into new biomes as well as provide decoration from the respective biome.

Mod spotlight by Welsknight!

https://www.youtube.com/watch?v=GMTDpcXgkyM

Currently the following biomes are supported:

• Plains - Can generate grass, flowers as well as Birch or Oak trees. - Converts the biome to Plains
• Desert - Creates varying size of cacti and dead bushes - Converts the biome to Desert
• Mesa - Creates an island of layered hardened clay of various colors as well as red sand and cactus - Converts the biome to Mesa
• Taiga - Creates an island of dirt, podzol, coarse dirt and grass with spruce saplings on the surface. - Converts the biome to Cold Taiga (Allows snow) 
• End - Creates an island of end stone with ruin-like structures of obsidian spotted about. - Converts the biome to End
• Nether - Creates an island of Netherrack, soul sand and gravel. Can spawn mushrooms if dark enough. - Converts the biome to Hell
• Mushroom Island - Creates an island of Mycelium with red and brown mushrooms with a chance to spawn large mushrooms. - Converts the biome to Mushroom island
• Ice Plains Spikes - Creates an island of snow and stone with randomized structures and pillars of packed ice. Converts the biome to Ice Plains.
• Jungle - Creates an island of grass and dirt with chances to spawn jungle "bushes", trees, melons and grass. Converts the biome to Jungle.
• Swamplands - Creates an island of grass and dirt with a chance to spawn trees and flowers. Can spawn pools of water with a chance to spawn clay deposits, lilypads, or sand and sugarcane.  Converts the biome to Swamplands
• Savanna - Plains-like foliage with Acacia and tall grass. Converts biome to Savanna
• Roofed Forest - Dense foliage with large Dark Oak and tall grass. Converts biome to Roofed Forest

How it works:

• A platform is generated underneath the player and blocks are generated in the world from the player one radius length away on all sides. Blocks will **only** be placed where air exists. It will not destroy any blocks if you accidentally cast it in an undesired location.
• After a circle is created, the platform begins to expand downwards in a spike-like shape with random chances to generate extra blocks where they otherwise would not - this gives the island a random shape.
• The surface is randomly distributed with various odds of decoration or blocks depending on the biome type chosen
• Once the surface is placed, the biome is then changed to the biome type of the crystal respective to each surface blocks column. It does  not change the entire chunk to the same biome. This lets you make really cool biome borders!
• Decoration and biome shifts only happen on newly generated surface blocks. Casting it without generating new surface won't do anything!
• The item is damaged based on the number of blocks generated, not the number of casts.
• Configuration to enable ore gen and stone for lower layers is available. 

Diameter, durability, decoration, ore gen, stone layers and biome conversion are all configurable in the configs giving pack authors the utmost control!

An example of how the island generates: https://gfycat.com/AdvancedImpracticalKookaburra

 Modded biome support added in this mod: http://minecraft.curseforge.com/projects/terrain-crystals-add-ons