Looking like a stegosaurus with long, sharp spikes instead of plates along its back and tail, these dwell mainly in areas of heavy vegetation.
Originally Posted by Shade of the En World forums.
This strange quadruped has a horizontal body with small bony plates on its back up to its hind legs. From this point leading down to the tail, it has long, sharp spikes. Its head is small and horse-like, and its pebbly skin is marked with stripes.
Dacentrurusis one of the more primitive stegosaurs, whose descendants include stegosaurus and kentrosaurus.
A dacentrurus is about 15 feet long and weighs up to three tons. They are docile herbivores, browsing through jungles and scrub forests in small herds. If provoked, however, they are deadly, lashing out with their spiked tails.
|Hit Dice||9d8+54 (94 hp)|
|Speed||30 ft. (6 squares)|
|Armor Class||17 (-2 size, -1 Dexterity, +10 natural), touch 7, flat-footed 17|
|Attack||Tail spike +17 melee (3d6+15/19-20/x4)|
|Full Attack||Tail spike +17 melee (3d6+15/19-20/x4)|
|Space/Reach||15 ft./10 ft.|
|Special Attacks||Augmented critical|
|Special Qualities||Fortification, Low-Light Vision, Scent, spiny defense|
|Saves||Fort +14, Ref +5, Will +6|
|Abilities||Strength 31, Dexterity 9, Constitution 23, Intelligence 1, Wisdom 13, Charisma 4|
|Skills||Listen +9, Spot +9|
|Feats||Alertness, Great Fortitude, Iron Will, Weapon Focus (tail spike)|
|Organization||Solitary, pair or herd (4-7)|
|Advancement||10-18 HD (Huge), 19-27 HD (Gargantuan)|
If threatened, a dacentrurus will assume a defensive position, always keeping its tail facing its enemies. If badly outnumbered or surrounded, it flees, as it is both weaker and faster than its larger kin.
Augmented Critical (Ex): The spikes on the tail of a dacentrurus are keen and as sharp as picks. They threaten a critical hit on a 19-20 and deal x4 damage on a successful critical hit.
Fortification (Ex): The bony plates on the neck and shoulders of a dacentrurus help to protect its spine from injury. Any critical hit or sneak attack made against the dacentrurus has a 10% chance of failing, dealing only normal damage.
Spiny Defense (Ex): Any creature that hits a dacentrurus in melee using a handheld or natural weapon (but not a reach weapon) must succeed on a DC 13 Reflex save or take 1d6+6 points of damage from the creature’s broad spines. The save DC is Dexterity-based.
Originally appeared in Monster Manual II (1983).