Death Burst. When the golem dies, it explodes in a burst of jagged teeth, and each creature within 30 feet of it must make a DC 20 Dexterity saving throw, taking 45 ( 10d8 ) bludgeoning damage on a failed save, or half as much damage on a successful one. The area of the explosion becomes difficult terrain for the rest of the encounter.   Necrotic Absorption. Whenever the golem is subjected to necrotic damage, it takes no damage and instead regains a number of hit points equal to the necrotic damage dealt.   Immutable Form. The golem is immune to any spell or effect that would alter its form.   Magic Resistance. The golem has advantage on saving throws against spells and other magical effects.   Magic Weapons. The golem's weapon attacks are magical.   Biting Aura. The golem can occupy another creatures space. Any creature that starts its turn in the same space as the golem or adjacent to it (within 5 feet) automatically takes 10 necrotic damage or 20 when the golem is bloodied.