Earthquake

Earthquake
Spell Information
Spell level :	Innate level: 8, Cleric: 8, Druid: 8
School :	Evocation
Components :	Verbal and Somatic
Range :	Long
Target/Area :	Huge
Duration :	Instant
Save :	Reflex 1/2
Spell resistance :	No

Description

You cause a massive earthquake around an area, causing 1d6 points of bludgeoning damage per caster level (to a maximum of 10d6) to all creatures in the area of effect. You are not affected by the earthquake.

Gameplay Notes

Since Earthquake is an 8th level spell, clerics and druids do not normally gain access to it until 15th level, thus the spell will always inflict 10d6 points of damage; i.e. it already reaches its cap before a caster gets access to it.

Although not mentioned in the spell's description, all creatures in Earthquake's area of effect must succeed on a DC 15 Reflex save or be knocked down for one round; Evasion and Improved Evasion are not used to determine the outcome of this Reflex save.

Additionally, and also not mentioned in the spell's description, any creature that is casting a spell when hit by Earthquake (even if it takes no damage) must succeed on a DC 28 (20 + Earthquake's spell level, which is 8th) Concentration check or lose the spell it was casting and suffer 100% spell failure for one round.

The spell is not supposed to affect the caster, yet the caster is not excluded properly, this is extremely problematic when an enemy is dominated and then casts this spell, because any hostile AoE magic affecting dominated associates will immediately dispel the dominated effect (even if the spell is cast by the dominated creature itself!), returning the enemy to their original faction. It seems that the problem is caused by signalling the casting of the harmful spell to the caster (line 82: SignalEvent...). To fix, exclude the caster as early as possible (X0_S0_Earthquake script):

if (spellsIsTarget(oTarget, SPELL_TARGET_STANDARDHOSTILE, OBJECT_SELF) && oTarget != oCaster)