Brute A melee weapon deals one extra die of its damage when the bugbear hits with it (included in the attack)
Surprise Attack If the bugbear surprises a creature and hits it with an attack during the first round of combat, the target takes an extra 2d6 damage from the attack.
Long-Limbed When the bugbear makes a melee attack on its turn, the attack's reach increases by 5 ft.
Rage Aard can enter a rage as a Bonus Action. During this state he has: Advantage on Strength checks and Strength Saving Throws; a +2 bonus to the damage roll (included in the attack Resistance to Bludgeoning, Piercing and Slashing damage.
Danger Sense Aard has advantage on Dexterity Saving throws against traps and spells he can see.
Reckless Attack Aard can gain Advantage on his Attack Rolls, at the cost of granting advantage on attacks made against him.