Elder Mokele-Mbembe (5e Creature)
From D&D Wiki
Gargantuan , unaligned
Hold Breath. The Elder Mokele-Mbembe can hold its breath for 30 minutes.
Trampling Charge. If the Elder Mokele-Mbembe moves at least 20 feet straight toward a creature and then hits it with a gore attack on the same turn, that target must succeed on a DC 21 Strength saving throw or be knocked prone. If the target is prone, the Elder Mokele-Mbembe can make one stomp attack against it as a bonus action.
Multiattack. The Elder Mokele-Mbembe makes three attacks: two with its Stomp and one with its Tail.
Stomp. Melee Weapon Attack: +11 to hit, reach 5 ft., one prone creature. Hit: 35 (5d10 + 7) bludgeoning damage.
Tail. Melee Weapon Attack: +11 to hit, reach 40 ft. Hit: 30 (4d8 + 7) bludgeoning damage. If the target is a creature, it must succeed on a DC 21 Strength saving throw or be knocked prone.
Elder Mokele-Mbembe are the greatest of their kind. These massive creatures are known to ford across bays and seas just to make their way to the great jungles on the continents and swim at leisure among rivers, lakes and swamps devouring all manner of vegetation whether it's ferns, tree leaves, marsh grass, cactus...etc. Even the most poisonous plants and fungi barely phase these Titanic herbivores. No know natural predators can slay a Elder Mokele-Mbembe and whole tribes of humans and humanoids have built small villages on their backs using them as transportation from Island to Island or river bank to river bank. These creatures are known to get angry in mating season and will happily knock over boats or canoes that they deem are in their territory. Generally these beasts prefer to sleep mostly submerged aside from their nostrils on the top of their heads gently poking above the water. People who are not aware of this might think that they have caught a sleeping shoft shell turtle... many villagers have been slain thinking they caught themselves a tasty morsel.
The only thing that has successfully killed these titanic beasts are Tyranosaurus Rex packs or packs of other huge predators. If they can get a hold on the beast via biting or grappling they can stop a majority of it's deadly attacks while the rest of the pack disembowel the mighty Titanosaur from both flanks. Still it can take an entire hour to kill the Elder Mokele-Mbembe.