Adult Silver Dragon

If the monster fails a saving throw, it can choose to succeed instead.

The monster makes three Rend attacks. It can replace one attack with a use of (A) Paralyzing Breath or (B) Spellcasting to cast Ice Knife.

Melee Weapon Attack: +13 to hit, reach 10 ft., one target. Hit: 16 (2d8+8) slashing damage plus 4 (1d8) cold damage.

The monster exhales a 60-foot cone of cold. Each creature in the area must make a DC 21 Constitution saving throw, taking 54 (12d8) cold damage on a failed save, or half as much damage on a successful one.

The monster exhales a 60-foot cone. Each creature in the area must make a DC 20 Constitution saving throw. On a failed save, a creature is incapacitated until the end of its next turn, when it repeats the save. On a second failed save, the creature is paralyzed for 1 minute, repeating the save at the end of each of its turns, ending the effect on a success. After 1 minute, it succeeds automatically.

The monster casts one of the following spells, requiring no material components and using Charisma as the spellcasting ability (spell save DC 19, +11 to hit with spell attacks): At will: Detect Magic, Hold Monster, Ice Knife, Shapechange (Beast or Humanoid form only, no Temporary Hit Points gained from the spell, and no Concentration or Temporary Hit Points required to maintain the spell) 1/day each: Ice Storm (level 5 version), Zone of Truth