4. In this setting most sorcerers are power-mad, misanthropic and ruthless (in a word, evil). Something intrinsic in the magic system should either favor evil or should lead to the corruption of its practitioners. Spellcasters are feared and reviled.
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16. The written magical language, such as is found in sorcerer’s grimoires, is not a complete language unto its own. Magical writings are composed of both standard modern or ancient languages and magical runes. To understand the writing, a character must be able to read the magic runes and the base language.
17. Learning a new spell from another caster or a spellbook requires 2 days of dedicated study per spell level and a Spellcraft check with a DC of 15 + 2 per spell level. Spellcraft checks will be modified by the quality and comprehensiveness of the caster’s notes and/or instruction. The DM will inform players of any modifiers prior to the character’s attempt to cast the spell.
Whether the spell is correctly and fully understood is not known until the caster first attempts to cast it. Failing to master the otherworldly forces of magic exacts a heavy toll from the caster. The caster takes 3 CON of temporary ability damage per spell level of the failed spell. Casters take 2 CON of temporary ability damage when failing to correctly cast a 0-level spell. A character cannot retry to learn the spell until he improves his Spellcraft skill.
18. Demonic spellcasters who are not Chaotic Evil have a Corruption statistic. Every time a demonic spell is cast the spellcaster must make a Will saving throw at a DC of 11 + spell level. If the spellcaster fails the saving throw, his Corruption statistic is increased by 1 point. This represents that the spellcaster did not fully master the demons he encountered in drawing arcane might and was corrupted by the mad cruelty of the Teeming Swarmlands. When the spellcaster’s Corruption statistic reaches a multiple of 25, his alignment moves one step toward Chaotic Evil. The axis that is furthest from Chaotic Evil will change. If both axes are the same distance from Chaotic Evil, the character may choose which axis to change. For example, if a Lawful Neutral character’s Corruption statistic has just reached 25, he becomes corrupted and his alignment must change to True Neutral (because Lawful is two steps from Chaotic, whereas Neutral is only step from Evil). If the character’s Corruption statistic reaches 50, he becomes further corrupted and the character may choose whether to become Neutral Evil or Chaotic Neutral.