GURPS Divination: part 1

For those of you not familiar with the GURPS Magic System, here's an overview. The spells are divided into colleges, such as Animal, Mind Control, Necromantic, Elemental: Air, Elemental: Fire, Food, Healing, and so on. Most spells have a prerequisite. That is, you need to learn certain other spells before you can learn this one. In each college, there are one or more "basic" spells, that anyone can learn (only mages can actually cast the spells unless you're in a high mana zone, but anyone can learn them). These basic spells are very simple spells with no prerequisites, and in turn are the prerequisites for more powerful spells, which are the prerequisites for even more powerful spells, and so on.

Some have options ("Hide" can be learned using either "Forgetfulness" or "Blur" as prerequisites), some have non-spells ("Activate Runes" requires the "Rune Lore" skill), and some spells require that you be a mage (that is, you have purchased the "Magical Aptitude" advantage). Some spells require a certain number of spells from a specific college, but it doesn't matter what those spells are.

I mention this because I want to discuss the "Divination" spell. The spell itself is pretty straightforward: you cast the spell, and if successful, you receive answers to a question concerning the future. The exact method of doing this varies, and the prerequisites for the spell depend on the method you choose for your character to cast the spell. It lists several examples, from the mundane and standard (such as Astrology, Crystal-gazing, Tarot) to common but less mundane (such as Haruspication – examining the entrails of an animal) to the less common (Belomancy – throwing a bunch of arrows into the air and divining the answer from the pattern in which they land) to the bizarre (Molybdomancy – pouring molten lead into cold water and examining the resulting shapes).