20 (natural armor)
350 (20d20 + 140)
40 ft., burrow 40 ft.
Con +15, Int +6, Wis +9
Perception +7
poison, psychic; bludgeoning, piercing, and slashing from nonmagical attacks
charmed, frightened, prone
blindsight 90 ft., tremorsense 90 ft.
Terran
25
If the giant sand shark fails a saving throw, it can choose to succeed instead.
The giant sand shark has advantage on saving throws against spells and other magical effects.
The giant sand shark deals double damage to objects and structures.
The giant sand shark can burrow through solid rock at half its burrow speed and leaves a 10-foot diameter tunnel in its wake.
Melee Weapon Attack: +16 to hit, reach 15 ft., one target. Hit: 43 (6d10 + 10) piercing damage. If the target is Large or smaller it must succeed on a DC 18 Dexterity saving throw or be swallowed by the giant sand shark. A swallowed creature is blinded and restrained, it has total cover against attacks and other effects outside the giant sand shark, and it takes 21 (6d6) acid damage at the start of each of the giant sand shark's turns. If the giant sand shark takes 40 or more damage in one turn from a creature inside it, the giant sand shark must succeed on a DC 19 Constitution saving throw at the end of that turn or regurgitate all swallowed creatures, which fall prone within 10 feet of the giant sand shark. If the giant sand shark dies, a swallowed creature is no longer restrained by it and can escape from the corpse using 20 feet of movement, exiting prone.
The giant sand shark can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. The giant sand shark regains spent legendary actions at the start of its turn.
The giant sand shark makes a Wisdom (Perception) check.
The giant sand shark makes a bite attack.
The giant sand shark moves up to its speed without provoking opportunity attacks.