Keen Smell. The double bear has advantage on Wisdom (Perception) checks that rely on smell.

Demonic Eruption. When the double bear is reduced to 0 hit points, its belly bursts open and an demon erupts from it. The demon resembles a hairless, decaying bear with two heads. It has the statistics of a double bear, except for these differences:

• When it uses Multiattack, it makes two bite attacks and one claw attack.
• Its creature type is fiend (demon).
• It does not have Demonic Eruption.

(This demon is included in the double bear's Challenge Rating.)

Multiattack. The double bear makes two attacks: one with its bite and one with its claws.

Bite. Melee Weapon Attack: +10 to hit, reach 10 ft., one target. Hit: 15 (2d8 + 6) piercing damage.

Claws. Melee Weapon Attack: +10 to hit, reach 10 ft., one target. Hit: 20 (4d6 + 6) slashing damage.

Warp World (3/day). The double bear creates the effect of the hallucinatory terrain spell. The save DC for this effect is 12.

Unearthly Roar (1/day). Each other non-demon creature within 40 feet of the double bear has its mind split in two. At the end of each of its regular turns, an affected creature must make a DC 12 Charisma saving throw. If it fails, it takes an extra turn, but its actions during that turn are controlled by a malign fragment that seeks to destroy all other non-demons it can see. Two successful saving throws end the effect.

If the creature is subjected to a second Unearthly Roar while its mind is split, the malign fragment takes physical shape and bursts out of its body, dealing 18 (4d8) points of slashing damage. It then becomes a demon of CR 7 or less, and the split mind effect ends.