Crafting Editblue topaz, and 1 glass block.
Important: You must create an Arcane Compendium in order to access this block. Otherwise, you will get the message: "You cannot comprehend what you see inside the Occulus" or "Mythic Forces prevent you".Edit
In each of these spell trees, there are various shapes (square), which define what a spell is going to do. There are 3 basic ones: Projectile, which shoots a projectile, Touch, which effects blocks or other objects directly in front of you, and Self, which applies effects to your person. Others can be unlocked further on with additional points.
Each spell tree also has a large variety of components (octagon), which give a spell certain qualities, such as damage, buffs, or effects, like fire damage, a plow, or perhaps invisibility. More difficult components are unlocked further on down the tree, along with other pieces.
The last natural piece in each spell tree is the modifiers (diamond), which will change how a given spell works. For example, a bounce modifier will make a projectile bounce a given number of times before disappearing, as a gravity modifier will allow it to be affected by gravity. Some modifiers effect damage, or mining, or other potential abilities.
The greatest components of spells that can be unlocked are called Silver Spells. They are found off to the left side of a page in the occulus, not attached to the tree, and require you to create and cast a specific spell to unlock. The most desired of these silver spells is Firestorm, which rains a hail of fire down over a period of seconds that will annihilate any lesser mob that has the bad luck to be caught in it. The rest are up to you to find and unlock.
See the Interactive Occulus Skill Tree for more information on the available spell parts.