Giant, Hellfire

Death Malison. When it dies the runes on its body flash a bright green then turn to mundane malachite. Each creature within 20' of giant: cursed 7 days (DC 16 Con negates) or until lifted by remove curse spell or similar. While cursed creature has disadvantage on saves and on first attack roll it makes on each of its turns. Fiends have disadvantage on the save.

Rune-Powered Weapons. Its weapon attacks are magical. When it hits with any weapon weapon deals extra 2d8 fire (included in below).

Stone Camouflage. Advantage on Dex (Stealth) checks made to hide in rocky terrain.

Multiattack. Two Greatclub or Runic Blast attacks.

Greatclub. Melee Weapon Attack: +10 to hit, 15 ft., one target, 19 (3d8+6) bludgeoning damage + 9 (2d8) fire.

Runic Blast. Ranged Spell Attack: +7 to hit, 60 ft., one target, 25 (4d10+3) force and target's speed halved until end of its next turn (DC 16 Con not half speed). Fiends have disadvantage on the save.

Invisibility Rune. Magically turns invisible until it attacks or until its concentration ends (as if concentrating on a spell). Any equipment the giant wears or carries is invisible with it.

Runic Shield. Adds 4 to its AC vs. one attack that would hit it as green runes encircle the giant. To do so giant must see the attacker and can't be invisible