Anathema: bring civilization to intrude on the wild, create undead, despoil areas of natural beauty
Using metal armor or shields.
Despoiling natural places.
Teaching the Druidic language to non-druids.
Polluting the air or allowing those who cause major air pollution or climate shifts to go unpunished
Special abilities:
Keen Eyes: Your eyes are sharp, allowing you to make out small details about concealed or even invisible creatures that others might miss. You gain a +2 circumstance bonus when using the Seek action to find hidden or undetected creatures within 30 feet of you. When you target an opponent that is concealed from you or hidden from you, reduce the DC of the flat check to 3 for a concealed target or 9 for a hidden one.
Watchful Halfling: You gain a +2 circumstance bonus to Perception checks when using the Sense Motive basic action to notice enchanted or possessed characters. If you aren't actively using Sense Motive on an enchanted or possessed character, the GM rolls a secret check, without the usual circumstance and with a –2 circumstance penalty, for you to potentially notice the enchantment or possession anyway.
In addition to using it for skill checks, you can use the Aid basic action to grant a bonus to another creature's saving throw or other check to overcome enchantment or possession.
As usual for Aid, you need to prepare by using an action on your turn to encourage the creature to fight against the effect.
Wildwood Halfling: You ignore difficult terrain from trees, foliage, and undergrowth.