The Hierarchy of Forests, or Forest Feudalism

Royal forests are cool. From Wikipedia:

"...under the Norman kings (after 1066), by royal prerogative forest law was widely applied. The law was designed to protect the venison and the vert, the "noble" animals of the chase – notably red and fallow deer, the roe deer, and the wild boar – and the greenery that sustained them. Forests were designed as hunting areas reserved for the monarch or (by invitation) the aristocracy (see medieval hunting). The concept was introduced by the Normans to England in the 11th century, and at the height of this practice in the late 12th and early 13th centuries, fully one-third of the land area of southern England was designated as royal forest; at one stage in the 12th century, all of Essex was afforested, and on his accession Henry II declared all of Huntingdonshire forest."

Royal forests, by nature of their creation and mode of use, are special places. Perhaps more so than anywhere else in the land, they are places where the king and his nobles leave their mark. Anyone can take and hold a castle, it's just a pile of stones, but if anyone can hunt in a royal forest then it ceases to be a royal forest. That's why poaching in a royal forest is punished so harshly - it's both a physical and spiritual theft against majesty itself. Naturally, royalty infuses these places and enforces its own indelible order on its inhabitants in a mirror of mankind's feudal society:

• Kings & Queens (Stags & Does)
• Dukes and Counts (Bucks)
• Barons (Boar)
• Knights (any animal that seems particularly noble and doesn't fit into the other categories)
• Peasants (other prey species)
• Outlaws (Wolves, Bears)

 Maybe the examples below are literal. Maybe they're metaphorical. Maybe they're both.

Stag King

Satoshi Matsuura

A braying call heralds the charge of the King of the Forest, and the forest bows to his will. A shining aura surrounds him as he thunders towards you, glittering antlers rearing skyward. None feel the influence of the glory of royalty more than deer, the favoured hunt of monarchs.

AC: Plate, HD: 8, Attack: 2d8 lance + Save or be thrown 30ft into the air, Move: 50', Morale: 10, Special: Aura of Royalty - when first encountered any foreign (to the forest) creature must Save or abase themselves before the King of the Forest.

Interesting things: Gilded antlers, royal lance, oak-pattern royal seal, briar-walk boots.

Boar Baron

Satoshi Matsuura

A muffled grunt echoes from across the clearing. Then again, and again, rising in tempo until reaching a screeching squeal. The heavy-bodied baron and his retainers close in for the kill, froth at their lips and bloodlust in their eyes. The King of the Forests trusts his barons to police his lands and guard his borders.

AC: Chain, HD: 6, Attack: 1d8 sword + Save or bleed, Move: 30', Morale: 10, Special: Blood-scent - the baron can sniff out the scent of any wounded outsider within 3 miles.

Interesting things: Fortifying fats, razor tusks, engraved nose-ring, armoured bristles.

Otter Knight

Satoshi Matsuura

Lost and tired, your party stops by a river to make camp and rest. You think you're safe, but when you go to draw water from the river you see too late the glimmer of steel beneath the surface.

AC: Chain, HD: 4, Attack: 1d6 sword, Move: 30'/Swim 60', Morale: 8, Special: Water walk - when immersed, the otter knight can move to another body of water within 1 mile as a full action. This works in a river, stream or pond, but not in a bucket.

Interesting things: Gill helm, insulating coat, swimming boots.

Beaver Man-at-Arms

Satoshi Matsuura

It is a lord's right to charge a toll to all those who cross his bridges while in his domain. The lords of the forest entrust the construction and wardship of these vital passages to trusted servants, and none are more trusted in this matter than the beavers. Their blunt demeanours and stout axes are more than required to ensure that travellers pay up.

AC: Chain, HD: 3,  Attack: 1d6 axe/1d8 crossbow, Move: 30'/Swim 60', Morale: 8, Special: Woodworker - instead of dealing damage, the beaver man-at-arms can instead choose to destroy an opponent's wooden shield with a swift bite of their teeth.

Interesting things: Bag of bridge fares, waterproof oiled pouch, plans for a nearby fortification.

Fox Verderer

Satoshi Matsuura

Although the King of the Forest does not hunt, he nonetheless holds swathes of the forest for himself. He entrusts his chosen servants to maintain these lands in his absence, and to catch and punish those who would wrong him. The crafty fox serves him well in these matters, stalking criminals silently and administering the king's justice swiftly.

AC: Leather, HD: 2, Attack: 1d8 longbow/1d6 cudgel, Move: 50', Morale: 8, Special: Shadowstep - instead of a move action, the fox verderer may teleport to a spot 30' away.

Interesting things: A nefarious trap, seeker arrow, map of hidden trails in this area.

Bear Outlaw Boss

Satoshi Matsuura

The wolves and bears both reject the King of the Forest's claim to the throne, and their mutual enmity can sometimes be put aside in pursuit of mutual raids. A grown bear is a fearsome foe, and even more so when drunk on blood-mead, wielding weapons of awesome size and surrounded by clouds of bees that nest in their armour. Few can stand against them.

AC: Plate, HD: 6, Attack: 2d8 greatsword, Move: 30', Morale: 10, Special: Stinging cloud - the bear outlaw boss emits a cloud of angry bees when struck. All targets engaged in melee for the next turn attack with disadvantage.

Interesting things: Horn of blood-mead, royal jelly comb, armoured pelt, rune-inscribed bear claw necklace.