Dire Tarrasque (5e Creature)
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Gargantuan monstrosity, unaligned
Saving Throws Int +5, Wis +9, Cha +9
Legendary Resistance (3/day) If the dire tarrasque fails a saving throw, it can choose to succeed instead.
Magic Resistance The dire tarrasque has advantage on saving throws against spell and other magical effects.
Reflective Carapace Any time the dire tarrasque is targeted by a Magic Missile spell, a line spell, or a spell that requires a ranged Attack roll, roll a d6. On a 1 to 5, the dire tarrasque is unaffected. On a 6, the dire tarrasque is unaffected, and the effect is reflected back at the caster as though it originated from the dire tarrasque, turning the caster into the target.
Siege Monster The dire tarrasque deals double damage to objects and structures.
Multiattack. The tarrasque can use its Frightful Presence. It then makes five attacks: one with its bite, two with its claws, one with its horns, and one with its tail. It can use its Swallow instead of its bite.
Bite. Melee Weapon Attack: +19 to hit, reach 10 ft., one target. Hit: 36 (4d12 + 10) piercing damage. If the target is a creature, it is grappled (escape DC 20). Until this grapple ends, the target is restrained, and the tarrasque can't bite another target.
Claw. Melee Weapon Attack: +19 to hit, reach 15 ft., one target. Hit: 28 (4d8 + 10) slashing damage.
Horns. Melee Weapon Attack: +19 to hit, reach 10 ft., one target. Hit: 32 (4d10 + 10) piercing damage.
Frightful Presence. Each creature of the tarrasque's choice within 120 feet of it and aware of it must succeed on a DC 17 Wisdom saving throw or become frightened for 1 minute. A creature can repeat the saving throw at the end of each of its turns, with disadvantage if the tarrasque is within line of sight, ending the effect on itself on a success. If a creature's saving throw is successful or the effect ends for it, the creature is immune to the tarrasque's Frightful Presence for the next 24 hours.
Swallow. The tarrasque makes one bite attack against a Large or smaller creature it is grappling. If the attack hits, the target takes the bite's damage, the target is swallowed, and the grapple ends. While swallowed, the creature is blinded and restrained, it has total cover against attacks and other effects outside the tarrasque, and it takes 56 (16d6) acid damage at the start of each of the tarrasque's turns.
The dire tarrasque 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 dire tarrasque regains spent legendary actions at the start of its turn.
Move. The dire tarrasque moves up to half its speed.
Chomp (Costs 2 Actions). The dire tarrasque makes one bite attack or uses its swallow.
Like a normal tarrasque, but made bigger by powerful wizards or the gods or whatever the DM feels like.