User:TheSatanicSanta/Mystcraft Wiki import/Materials

Material block pages modify a terrain generator (a "standard" world, cave world, floating island, etc.), or one of several "features" (or, before V12, populators and terrain alterations), such as obelisks or floating islands.

Material types do not blend like most modifiers. Instead, the grammar collects them on a (sort of) stack until they are "picked up" by an appropriate primary symbol. Different symbols have various restrictions for the materials they can use, but each will accept the most recent appropriate material.

Obelisks, spheres, and such can be almost any solid block, while either sort of lake can be almost any fluid block but (most) terrain controllers choose a "land" block and a "sea" block from more limited sets. Notably, ores do not qualify as terrain blocks, nor do such materials as Stone Brick. Similarly, a "sea" block must be a liquid, ice, packed ice, or the special No Seas symbol. Mod liquids may or may not be usable for a world's seas, but even a "seabanned" liquid can be used for lakes. However, using a valuable material (ores or many mod liquids) for a feature can produce major instability.

If you write reasonably, you should not need to worry too much about the details. It's wise to put modifiers immediately before what they're intended to modify, just to keep things straight and minimize unfortunate incidents. While you can get away with writing "Stone Block, Oak Wood Block, Tendrils, Spheres", it's much safer to write "Stone Block, Spheres, Oak Wood Block, Tendrils" for the same results, and be clear about which material goes with which structure.