Link

Area 
Postpones the activation of one or more linked spells cast in its area of effect, until a certain thing happens in the Link’s presence. This triggering event may be as simple or complex as the caster desires, and is governed like Delay. The Link may also be triggered by the activation of a spell placed on the area after the Link, such as Watchdog, Delay or another Link.

The caster pays the energy costs and makes the skill rolls for the Link spell and all linked spells at the time of casting. Linked spells may not benefit from cost reductions for high skill. If the intended subject of a linked spell is not present at the time of casting, there is an additional -5 penalty for the linked spell (but not for the Link) for not being able to touch or see the subject – see p. 11.

The size of the area of the Link spell is determined at the time of casting. Any linked spells may go off anywhere within the Linked area; for instance, if a one-yard-radius Create Fire and one-yard-radius Glue spell were linked to a 20-yard-radius Link to catch intruders, the first intruder to enter the Link’s area would find himself in a zone of flaming glue, but subsequent intruders would be safe (from that Link, anyway). The size of the linked spells must be set at the time of casting. If the subject is larger than the estimated target, the spell either has no effect, or a weaker effect, depending on the spell. The GM’s ruling on this is final.

Only subjects within the Linked area are affected, unless the spell results in an effect that would not be bound to that area – summoning a demon, for example! The triggering event may occur outside of the area, however. The time to cast the linked spells is spent when initially set up. There is no delay when the Link is triggered – all linked spells are activated instantly. The linked spells do not count as a spell “on” for any purpose. Every three

Link spells on count as one spell on, rounding down. A mage cannot detect a Link simply by looking at it. The Mage Sight spell or the Detect Magic spell will reveal the Link, however.

If the mage knows the Conceal Magic spell, the Link may be made harder to detect by magical means. Simply adding the Conceal Magic costs to the base cost of the Link spell accomplishes this effect. The mage must know Conceal Magic to use this option. If the subject of a linked spell is not present at the casting, and has Magic Resistance, refer to the original die roll to determine the results. If the original die roll of the linked spell is not recorded, reroll the spell for this purpose only. Blocking and missile spells cannot be Linked – other spells can. An “instantaneous” spell like Thunderclap will happen once, when activated; then the spell will be gone. A continuing spell like Voices will start when activated, and then operate until it expires. A single Link can be made to activate a spell when the area is entered, and deactivate the spell when the area is left. This may continue until the linked spell expires. As an example, a mage may cast Link on Continual Light. If he then rolls seven days for the duration of the Continual Light spell (168 hours), he can have the Link set up to turn the Light on when he enters the room, and turn it off when he leaves. When 168 hours of light have been used, both spells expire. For instantaneous spells, the Link vanishes after activating the other spells.

No maintenance of a Link is required, either for the Link itself, the  linked spells, or any information spells cast on the Link to tell it when to trigger. Link may also be set in reverse, to stop one or more spells when a triggering event occurs. In that case, the linked spell will last only while the caster maintains it, but the Link itself requires no maintenance. Link can also be used for Limiting Enchantments (see pp. 68-69).

Duration: Until triggered, and its linked spells expire. 
Base cost: 8; linked spells cannot be maintained. 
Time to cast: 4 hours – there is no reduction in time to cast, no matter how well Link is learned. 
Prerequisite: Delay.

Item 
This spell may be cast permanently on any enchanted item, to determine the circumstances under which it works. The Limit spell would be used to determine the class of users that could use the item, but Link might be used, for instance, to make it work only at night.  Energy cost to cast: 200. Any Information spells required to tell it when to trigger (e.g., Detect Magic) must be cast as separate enchantments on the item. For instance, a sword might be Linked with a Light spell and a Sense Life spell, so that it would glow in the presence of orcs.

A reversed Link may be cast permanently on any enchanted item, to deactivate it under set circumstances. This is often used to keep magic items from falling into the wrong hands. 
Energy cost to cast: 200.