Binding is used to compel long-term services from a spirit that you’ve already summoned. This takes one hour per Force of the spirit and requires (Force x 25) drams of reagents to be used up in the binding. The test is an Opposed Binding + Magic [Force] v. spirit’s Force x 2, and it inflicts Drain equal to twice the hits (not net hits) on the spirit’s defense test, minimum 2. Additional net hits beyond the first add to the number of services the spirit owes.
Once the spirit is bound, then the spirit and its services do not expire at the next sunrise or sunset. A spirit’s service ends when it has no more services owed to the magician. The bound spirit can be called or dismissed with a Simple Action as they appear next to the magician from the metaplane, awaiting further instructions on the astral. A magician can bind up to his Charisma attribute in spirits.