Lovecraftian Spells: Making Magic Eldritch

From the introduction:

The driving force behind this supplement is not just to provide you with more spells for your game. Its purpose is to get you to think about the spells already at your disposal in different ways. What does barkskin look like when cast by a druid of the desert? The ocean? In order to differentiate regions, cultures, or sources of magic you need not create whole new spells. All you need is to tweak what you have!