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Magic 101
Natural Magic, Caster, Caster link, Juice, Scroll, Magic Item, Spell, Grandiocosmic Strings, Nodes

Proposed Canon

Grandiocosmic Strings or G-Strings are the conduits of all magic power in Erfworld. Only Thinkamancers know of their existance. The majority of (if not all) Thinkamancy Spells are actually the Thinkamancer manipulating the G-Strings of the other Units.

Speculation

Wanda Firebaugh might have some knowledge of Grandiocosmic Strings. Wanda is capable of handling a number of magicks outside Croakamancy including Thinkamancy Suggestion Spells and powerful scrolls that normally require a caster of a related discipline to implement. She also chanted the following song or poem in her attack on Ansom which hints strongly at the knowledge of threads or strings binding minds together:

"Rejoyce. Dispair. Fate does not care. Each knotted mind entwined. Each soul another's bind. And blind, though we are led, in time, we do know when to cut a thread!" ^Erf-b1-p119 (speech impediment removed)