Master Naturalist (3.5e Feat)
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Master Naturalist [General]
Your devotion to the natural world is all-encompassing, unifying your spellcasting ability.
Prerequisite: Ability to cast 1st-level divine spells, wild empathy.
Benefit: Your druid and ranger levels stack along with levels of other nature-based divine spellcaster classes when determining your caster level for all divine spells. For example, a 4th-level ranger/4th-level druid would have a caster level of 8th for both its ranger spells and its druid spells. Additionally, you gain a +3 bonus on all wild empathy checks.
Normal: Caster levels are tracked separately for each class and rangers have a caster level equal to half their ranger levels.
Special: When determining what constitutes a "nature-based" divine spellcaster class, the DM has final say. For example, a shaman may count, whereas most clerics may not.