All effects have specific durations. Some are instant, some last 5 minutes, some require a caster to concentrate, and so on. These durations are the same no matter what caused the effect. For instance, the duration of a Weakness is not dependent on whether it was caused by a spell or a gas.
The use of the word “caster” in the examples that follow includes anyone who caused the effect to come into use; for instance, a monster swinging “3 Web” would be the “caster” for purposes of the effect.
Concentration. This effect lasts as long as the caster maintains Focus. The recipient of a Concentration spell that requires physical requirements (such as arms crossed or in the air) may choose to decline the spell simply by not applying the physical requirements. All normal spell defenses must be used first.
For example: Vorin throws a Desecrate spell at Terin. Terin’s Spell Shield goes off. Vorin angrily throws another one at him. This one is effective, but Terin chooses not to have it affect him simply by refusing to cross his arms over his chest as required by the spell.
In no cases can these spells be used to force an unwilling target to break another spells’ physical requirements.
For example: Terin has a Repel active against Vorin. He holds his hand before him as required by the spell. Vorin throws a Desecrate at Terin, knowing he has no Spell Shield, in an attempt to disrupt the Repel. Terin merely chooses not to accept the Desecrate, and his Repel is still active.
Timed. Timed effects will end in a specific predetermined time, anywhere from five seconds to five days. If hit by two different timed effects, both will run at the same time.
For Example: Finther is hit by a Paralysis gas that will last five minutes. Two minutes later, he is hit by a Drain spell which also lasts five minutes. He is still paralyzed, but once the Paralysis wears off, he will be affected by the Drain for three more minutes.
You cannot have two of the same effect on you at the same time, so if you’re hit by two identical timed effects, the most recent one will always prevail.
Instant: The duration of this effect is instantaneous, but its effects may be permanent. Thus, any damage is permanent until cured.
Line of Sight. This effect lasts as long as the caster could see the victim from wherever the caster is located. It also lasts if the victim could see the caster. Basically, if you can draw a straight line between the caster and the victim without the line being obscured by any obstacles, then the Line of Sight is still in effect. The caster or victim cannot close his or her eyes or hide behind someone else to break Line of Sight.
If the caster or victim breaks Line of Sight by imposing a very large object such as a building or large tree between the caster and the victim for longer than five seconds, the spell is broken. If the view of the character is resumed before the five seconds is up, then the spell continues.
Storm: This effect type allows the caster to throw a number of packets as described in the specific effect. Unless otherwise specified, the caster may not move their feet during this time without breaking the effect. Each packet counts as its own effect for purposes of defensive abilities. In all other ways, these effects act as Concentration duration effects.
Note that a Storm spell can be cast/activated only on oneself and grants the target the ability to throw the packets. For example, someone with an activatable Magic Storm could activate the spell on themselves calling “Activate Spell Magic Storm!” and choose an element (such as Flame), after which they would throw 15 packets for “10 Spell Flame!” The Magic Storm spell itself is never thrown to be reflected, absorbed, etc., only the individual “10 Spell Flame!” packets are thrown.
While Storm spells may not be cast on other characters or Absorbed into rituals such as Spell Store, individual packets may be Absorbed if they exactly mimic an existing spell. For example, a Lesser Magic Storm packet for “10 Spell Flame” can be Absorbed into a Spell Store as a 2nd level spell, since it is exactly the same as a second level Evocation Bolt effect. However, a Mend Armor Storm packet for “10 Spell Mend Armor” cannot be Absorbed, since there is no existing spell effect that this duplicates (the 2nd level Mend Armor spell would be “20 Spell Mend Armor,” not 10).