n large animal 

Perception +13; low-light vision

Skills Acrobatics +7, Athletics +14, Intimidation +10

Str +6 Dex +1 Con +5 Int -4 Wis +3 Cha +0

AC  21; Fort +13, Ref +7, Will +11

HP 70

Speed 25 feet

Melee [>] talon +14 (agile), Damage 1d10 + 6 piercing plus Grab

Melee [>] beak +14, Damage 1d12 + 6 piercing

Bloodcurdling Screech [>] (fear, mental) Each creature within 80 feet who can hear the owlbear's screech must attempt a DC 20 Will save. The creatures can't be affected by another screech for 1 minute. On a critical success, the creature is unaffected; on a success, the creature gains the frightened 1 condition; on a failure, the creature gains the frightened 2 condition; on a critical failure, the creature gains the frightened 3 condition and must spend its next turn running away from the owlbear.

Grab [>] When the owlbear succeeds at its talon Strike, it can use this action immediately after to automatically give the target the grabbed condition until the end of its next turn.

Screeching Advance [>>] (auditory, fear, mental) The owlbear makes a Bloodcurdling Screech and Strides twice. All creatures within 80 feet of the owlbear at any point during this movement are subjected to the effects of Bloodcurdling Screech.

Beginner Box, page 74. Reprinted in TiO.