Bugbear Priest of Hruggek

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

Fury of Hruggrek. As a bonus action, when the bugbear hits a creature with a weapon attack, it can expend a spell slot to deal (1d8) poison damage to the target, and the target must succeed on a DC 14 Wisdom saving throw or be frightened until the end of the bugbear's next turn. If the bugbear expends a spell slot of 2nd level or higher, the extra poison damage increases by (1d8) for each level above 1st (maximum 5d8).  

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 7 (2d6) damage from the attack.

Spellcasting. The bugbear is a 10th-level spellcaster. Its spellcasting ability is Wisdom (spell save DC 14, +6 to hit with spell attacks). It has the following cleric spells prepared:
Cantrips (at will): resistance, sacred flame, thaumaturgy
1st level (4 slots): bane, healing word, shield of faith
2nd level (3 slots): augury, hold person, silence
3rd level (3 slots): dispel magic, glyph of warding, revivify
4th level (3 slots): banishment, freedom of movement
5th level (2 slots): contagion, flame strike

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

Blessing of Hruggek (3/day). The bugbear grants a +5 bonus to an attack roll made by a goblinoid creature it can see within 30 feet of it. If the goblinoid hits, it deals an extra 7 (2d6) poison damage. The bugbear can make this choice after the roll is made but before it hits or misses.