Aptonoth (5e Creature)
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Large beast, unaligned
Charge. If the aptonoth moves at least 20 feet straight toward a target and then hits it with a ram attack on the same turn, the target must succeed on a DC 12 Strength saving throw or be knocked prone.
Ram. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 6 (1d8 + 2) bludgeoning damage.
Tail. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 6 (1d8 + 2) slashing damage.
Aptonoth are large, cow-like herbivores that are more common than any other in the world. Found in many regions of the world in small groups as well as herds of hundreds, these dinosaurine grazers are not intimidating by any definition. While their crested heads can knock a man to his glutes, as can the spiked tail, they don't do much damage beyond that and an aptonoth's first instinct is usually to flee when attack. Otherwise, one could waltz right up to an alpha male and pet its nose with no consequences. It is their docile nature that has allowed aptonoth to be so easily domesticated, usually as a beast of burden or for meat.
Apceros are cousins of aptonoth, with tortoise-like heads, large horns projecting from their cheeks, a protective shell on their backs, a large mace-like tail club, and a terrible attitude. These desert dwellers regularly attack humanoids on sight, as they're highly territorial. Their infamous tactic of slowly stalking the intruder and tightly surrounding them to prevent escape has caused either the death or frustration of many a preoccupied adventuring band. Apceros have AC 16 from natural armor, the Aggressive trait, 18 Strength, and a vulnerability to lightning damage as opposed to fire. Otherwise, they have the same statistics as an aptonoth.