Once a regular northern forest, the Dullwood was corrupted by the influence of Celene and the tainted waters of the Churn, which fed the woods through several estuaries connected to it.
The denizens of the Dullwood include mutant animals and plants, things made more powerful (yet unstable) by the wild magic of the Churn. These beings are incredibly territorial, and hostile to anyone foolish enough to enter their domain.
It is largely avoided, even by the rough and tumble people of the Blight.
It is said that if a practitioner of the Art stays amongst the trees of the Dullwood long enough, their very spells become mutated and corrupt, acting unpredictably. Few have stayed in the woods long enough to test this theory.
Flora & Fauna
Unpredictable mutations run rampant throughout the woods, along with a variety of aberrations released from Celene during the Sundering. Never have the contents of the Dullwood been accurately documented, as all who've attempted never returned.
EXAMPLE MUTANT TEMPLATE
The following creature is a mutant hybrid of a large black bear and several other creatures fused to it on the molecular level...
Large abomination, chaotic neutral
Armor Class 17
Hit Points 168(16d12 + 64)
Speed 40ft., climb 20ft.
STR 19 (+4), DEX 16 (+3), CON 18(+4), INT 3(-4), WIS 14(+2), CHA 10(+0)
Skills Perception+6, Stealth+7
Senses Darkvision 90ft., passive Perception 16
Challenge 12 (8,400 XP)
Standing Leap. Long jump up to 30ft, and high jump up to 15ft, with or without a running start.
Multiattack. The mutant makes three attacks: one with its bite, one with its horns, and one with its claws. In place of bite or horns may instead constrict or use fire breath (if available).
Bite. Melee Weapon Attack: +8 to hit, reach 5ft., one target. Hit 11 (2d6 + 4) piercing damage.
Horns. Melee Weapon Attack: +8 to hit, reach 5ft., one target. Hit 10 (1d12 + 4) bludgeoning damage.
Claws. Melee Weapon Attack: +8 to hit, reach 5ft., one target. Hit 11 (2d6 + 4) slashing damage.
Constrict. Melee Weapon Attack: +8 to hit, reach 5ft., one target. Hit 15 (2d10 + 4) bludgeoning damage plus 15 (2d10+4) slashing damage. The target is grappled (escape DC 14) if not already constricting a creature, and the target is restrained until this grapple ends.
Fire Breath (Recharge 5-6). One mutant head (multiheaded) exhales fire in a 15ft. cone. Each creature in that area must make a DC15 DEX saving throw, taking 54 (12d8) fire damage on a failed save, or half as much damage on a successful one.
Not much can be taken from the woods, as any fruit from the trees has been corrupted by the Churn. The quality of the wood itself ranges from incredibly strong to completely worthless, and it's difficult to tell which at first sight.