Brute. A melee weapon deals one extra die of its damage when the bugbear hits with it (included in the attack).

Magical Dependency. If the zombified bugbear is in an anti-magic field, or if dispel magic is cast onto it, then it will immediately lose 10 hit points and will also have disadvantage on every check or save it must make. It also loses the ability to have an advantage on any check or save.

Uncanny Physique. The sight and smell of the zombified bugbear make the party members nauseous. All party members must make a DC 15 con save or be made nauseous - a condition that makes a player unable to willingly move closer to the source of its nausea, however they can still attack it with ranged attacks or if the source of the nausea approaches them. Necromancers, as well as players with an inability to smell, are immune to this effect. Once a player succeeds on a save against the nausea effect, then they are immune to the effect from all sources for the duration of the encounter.

Morningstar. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 11 (2d8 + 2) piercing damage.

Javelin. Melee or Ranged Weapon Attack: +4 to hit, reach 5 ft. or range 30/120 ft., one target. Hit: 9 (2d6 + 2) piercing damage in melee or 5 (1d6 + 2) piercing damage at range.