Phases of a Spell

There are a number of phases that a spell goes through during its lifetime which the spell crafter can utilize to design interesting behaviors: The phases are often called "Events" in the context of programming, so the terms may be used interchangeably.
 * Creation
 * Activation
 * Hit (Collision with an object)

Creation (On Create: orb)
This event occurs when the spell is first cast, and allows you to set up any initial behavior for the spell.

Activation (On Activate: orb)
This event occurs when the player presses the 'activate' key after a spell is cast. The activate event allows you set up delayed actions that occur on demand when the player requests it.

As shown by AureEntulava with TerraShift (here: https://the-codespells-forum.herokuapp.com/t/terra-shift-collect-move-and-easily-manage-the-crystals/156 ) OnActivate is also manageable, and can with a few inputs be made to do more than a single command.

Collision (On Hit: orb, other)
The event is triggered when the orb collides with any other object in the world, allowing you to set up interesting behaviors that interact with targeted objects.