Spellcasting. The dragon is a 5th-level spellcaster. Its spellcasting ability is Wisdom (spell save DC 14, +6 to hit with spell attacks). The dragon has the following cleric spells prepared:

Cantrips (at will): light, sacred flame, thaumaturgy

1st level (4 slots): cure wounds, guiding bolt, sanctuary

2nd level (3 slots): lesser restoration, spiritual weapon

3rd level (2 slots): dispel magic, spirit guardians

Multiattack. The dragon makes three attacks: one with its bite and two with its claws.

Bite. Melee Weapon Attack: +9 to hit, reach 10 ft., one target. Hit: 16 (2d10 + 5) piercing damage plus 5 (1d10) lightning damage.

Divine Claw. Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: 12 (2d6 + 5) slashing damage plus 10 (3d6) radiant damage.

Lightning Breath (Recharge 5–6). The dragon exhales lightning in an 60-foot line that is 5 feet wide. Each creature in that line must make a DC 16 Dexterity saving throw, taking 55 (10d10) lightning damage on a failed save, or half as much damage on a successful one.

Alter Shape. The dragon magically transforms into a eagle or a priest and retains its alignment, damage immunities, hit points, and Hit Dice, as well as its Intelligence, Wisdom, and Charisma scores. This transformation ends if the dragon is reduced to 0 hit points or if it uses another bonus action to end it.