Sources
CR
Type
Size
Alignment
Movement

Horizonback Tortoise

Gargantuan Monstrosity, Unaligned

Armor Class 17 (natural armor), 22 while in its shell
Hit Points 227 (13d20 + 91)
Speed 20 ft.
STR
28
+9
DEX
3
-4
CON
25
+7
INT
4
-3
WIS
10
+0
CHA
5
-3
Saving Throws STR +12, CON +10
Damage Immunities poison
Condition Immunities Poisoned
Senses darkvision 60 ft, passive Perception 10
Languages understands Goblin but can't speak
Challenge 8 (3,900 XP)

Traits

Amphibious. The tortoise can breathe air and water.

Massive Frame. The tortoise can carry up to 20,000 pounds of weight atop its shell, but moves at half speed if the weight exceeds 10,000 pounds. Medium or smaller creatures can move underneath the tortoise while it's not prone.

Any creature under the tortoise when it falls prone is grappled (escape DC 18). Until the grapple ends, the creature is prone and restrained.

Actions

Bite. Melee Weapon Attack: +12 to hit, reach 10 ft., one target. Hit:28 (3d12 + 9) bludgeoning damage.

Shell Defense (Recharge 4–6). The tortoise withdraws into its shell, falls prone, and gains a +5 bonus to AC. While the tortoise is in its shell, its speed is 0 and can't increase. The tortoise can emerge from its shell as an action, whereupon it is no longer prone.

Lore

Desolate badlands and soggy marshes are home to the ancient and massive horizonback tortoises of Eastern Wynandir. Nearly fifty feet from nose to tail, and with a habit of remaining stationary for long periods, a horizonback tortoise is easy to mistake for a low hill at a distance. But when these impressive creatures rise to begin their march, the sight inspires fear and awe in equal parts. An omnivore of incredible size, these scavengers prefer to feed on dead vegetation, but make use of…