Armor Class 23
Hit Points 553 (27d20 + 270)
Speed 60 ft.
Saving Throws DEX +8, WIS +8
Damage Resistances necrotic, radiant
Damage Immunities poison, psychic
Condition Immunities charmed, exhaustion, frightened, paralyzed, petrified, poisoned, stunned, unconscious
Senses Truesight 300 ft., passive Perception 10
Languages understands Celestial and Common but can't speak
Challenge 25
Immutable Form. The colossus can't shape-shift.
Legendary Resistance (4/Day). If the colossus fails a saving throw, it can choose to succeed instead.
Magic Resistance. The colossus has Advantage on saving throws against spells and other magical effects.
Siege Monster. The colossus deals double damage to objects and structures.
Multiattack. The colossus makes three attacks, using Slam or Radiant Ray in any combination.
Slam. m +18, reach 20 ft. Hit: 32 (4d10 + 10) Bludgeoning damage, and the colossus pushes the target up to 20 feet straight away from itself.
Radiant Ray. r +18, range 300 ft. Hit: 22 (4d10) Radiant damage. If the target is a Large or smaller creature, it has the Prone condition.
Divine Beam (Recharge 5–6). dex DC 26, each creature in a 300-foot-long, 10-foot-wide Line. 65 (10d12) Radiant damage. Half damage. A creature reduced to 0 Hit Points by this beam disintegrates into dust, leaving behind any magic items it was wearing or carrying.
Smite. The colossus makes one Radiant Ray attack.
Stomp. The colossus moves up to half its Speed without provoking Opportunity Attacks, and it can make one Slam attack at any point during that move.
Monster Manual (2024), p. 76