The behir is, simply, a predator. A huge monstrosity, in the neighborhood of 15 feet long, it’s fast, tough and strong, able to run as fast as a lion and to climb faster than most humanoids can run. Its Intelligence is at the upper end of animal range, and it’s a good judge of prey. It’s also surprisingly stealthy, able to strike from ambush and do spectacular damage to its victims.
But all this power comes at a cost: Behirs get sleepy as they digest their prey. Because of this, once a behir strikes and swallows its prey, it immediately breaks off and retreats to its lair or some other hiding place so that it can absorb its meal in peace.
Normally, a creature with a recharge ability prefers it over any other method of attack, but in the case of behirs, Lightning Breath is an oddly limited-use feature. Its range is only 20 feet, meaning that in most cases, it’s only likely to strike a single target (see “Targets in Area of Effect,” Dungeon Master’s Guide, page 249), and while the damage it does is substantial—about 50 points of expected damage—it doesn’t help the behir eat anything.
In contrast, the behir’s Multiattack comprises a Constrict action, which does an average of 34 points of damage and restrains its target on a hit, and a Bite action, which does an average of another 22 points of damage, with advantage on the attack if the target is restrained. That’s 56 points of damage right there, and the behir’s chance to hit is extremely high, compared with its chance of doing full damage with its Lightning Breath. Finally, on its next turn, it can Swallow the creature it’s restraining, which is what it came for. (more…)