Advanced Class: Druids, is the second supplement released by Silent7Seven. It is a three-page compilation of druid feats that represent the use of a single specialized animal shape that provides additional benefits. For example, you gain a bonus to Intimidate and bonus damage when you charge if you take Golden Pride and assume the shape of a lion. Outside of that form you retain the feat but gain no benefits at all.
Now, you are not limited in the feats you take and can specialize in more then one form. However, when you use wild shape to assume one of your "favored forms" you are unable to to wild shape into another form until the end of the encounter (or five minutes), but are free to shift back and forth between your favored form and natural form. This adds a tactical level of decision making for your druid, since normally wild shape does nothing mechanical except open up your Beast keyword evocations.
There are only two tiers of feats: heroic and paragon. The entry feats all grant a feat-based skill bonus (so will not stack with Skill Focus) in addition to an encounter attack or benefit of some sort. The paragon feats let you take on the form of a more fantastic beast, such as an umberhulk or red dragon, and grant an actual encounter power thematic to that creature. For example, Clawbeak Render lets you turn into an owlbear and grants a double-attack encounter power.
Essentially, Advanced Class: Druid is three pages of feats. I like the concept of a druid becoming so in tune to a specific animal form that she has a special mastery over it a lot. You could restrict these feats as techniques taught by certain druid circles, or to add emphasis to a theme. This supplement, however small, also provides some foundation for creating additional favored form feats and expanding upon them.
Now, in case Silent 7Seven checks this out, I have some requests for the next favored form supplement they make (which they can obviously take or leave).
I would have liked to see some paragon feats growing off of the heroic ones (such as a paragon lion-form feat that lets you rake an enemy if you hit with the charge attack), in addition to more heroic feats based off of the same animal form (such as another lion-form feat that lets you demoralize enemies with a powerful roar, once per encounter or even day). I would also consider making these (or future releases) into Multiclass feats that can replace existing druid powers. I think thats something that can be expanded upon in a really cool way, especially if you combine them with the Favored Form feats, you can really drive the point home that your druid prefers one form over another.
In addition, to avoid oversaturation of feats and allow more flexbile customization, make new powers that are thematic to specific animal forms.
All in all, this document is cheap, and by cheap I dont mean poor quality: I mean one dollar. Even for the poorest of gamers thats chump change and I think its easily worth the cost of what you are getting here, which is entirely crunch except for a single image on page 2. However, I will point out again that this is exclusively for druid players. There is absolutely nothing to see here if you arent interested or dislike the class. If you enjoy druids, I would certainly pick this up even just for conceptual groundwork.