The Reign Of Winter
Nature Bond (Ex): At 1st level, a druid forms a bond with nature. This bond can take one of two forms. The first is a close tie to the natural world, granting the druid one of the following cleric domains: Air, Animal, Earth, Fire, Plant, Water, or Weather. When determining the powers and bonus spells granted by this domain, the druid’s effective cleric level is equal to her druid level. A druid that selects this option also receives additional domain spell slots, just like a cleric. She must prepare the spell from her domain in this slot and this spell cannot be used to cast a spell spontaneously.
The second option is to form a close bond with an animal companion. A druid may begin play with any of the animals listed in Animal Choices. This animal is a loyal companion that accompanies the druid on her adventures.
Unlike normal animals of its kind, an animal companion’s Hit Dice, abilities, skills, and feats advance as the druid advances in level. If a character receives an animal companion from more than one source, her effective druid levels stack for the purposes of determining the statistics and abilities of the companion. Most animal companions increase in size when their druid reaches 4th or 7th level, depending on the companion. If a druid releases her companion from service, she may gain a new one by performing a ceremony requiring 24 uninterrupted hours of prayer in the environment where the new companion typically lives. This ceremony can also replace an animal companion that has perished.