Multiattack: Basically, this behir monster can make two attacks such as: one with its bite and another one with its constrict.
Bite: By using this bite attack this monster can make a Melee Weapon Attack: +10 to hit, reach 10 ft., one target. Hit: 22 (3d10 + 6) piercing damage.
Constrict: By using this constrict attack this monster can make a melee weapon attack +10 to hit, reach 5 ft., one Large or else a smaller creature. Hit: 17 (2d10 + 6) bludgeoning damage + 17 (2d10 + 6) slashing damage. The target has been Grappled (escape DC 16) suppose this behir monster is not already constricting one creature, and also the target has been Restrained until this grapple ends.
Lightning Breath (Recharge 5-6): This behir monster is exhales the line of the lightning which is 20ft., long and also 5 ft., wider. Each and every creature in that particular line should be capable of making a DC 16 Dexterity saving throw, also by taking 66 (12d10) lightning damage on a failed save, or else half as much damage on a successful one too.
Swallow: This behir monster can make a bite attack which is against to a Medium or smaller target that it is grappling. Suppose, the attack hits, the target has also been swallowed and then the grapple ends. During it has been swallowed, the target is Blinded and Restrained, it actually has total cover which is against to the attacks and some other effects outside of this behir, and also it takes 21 (6d6) acid damage at its start of each of behir’s turns. Basically, the behir has the capability to have only one creature which has been swallowed simultaneously.
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If the behir could take 30 damage or else more than on a single turn from a swallowed creature, but this behir must be succeeded on the DC 14 Constitution saving throw at an end of that specific turn or else regurgitate the creature, which has been falls prone in the space within a 10ft., of the behir. Whenever if this behir has been died, even a swallowed creature has o longer been restrained by this and also can escape from the corpse by simply using 15 ft. of Movement, exiting prone.