Fire elementals are immune to fire damage.

The fire elemental burns its opponents.

The fire elemental deals 1d6 damage to any creature that attacks it in melee.

The creature is barely affected by weapon damage: metal bounces off it like a mere piece of wood, or the creature heals immediately. It gains damage reduction (DR) 5, subtracted from all damage it takes.

On an attack roll of 15-20, if the attack succeeds, the victim must succeed on a Strength or Dexterity check (its choice), DC [10 + the creature's Strength modifier], or be Knocked Prone. The creature reduces all weapon damage it takes (melee or ranged) by 2 (damage reduction 2). Spells deal normal damage.

The creature uses its great size to affect several creatures in front of it with a single blow. If multiple targets are in front of it, its attack affects two creatures (in a 180° arc). Make a single attack roll and compare it to each target's armor class. Its damage reduction increases to 4.