I made this magma crocodile sometime ago. He has a extremely high body temperature, have basalt scales, can swim in magma and shoot balls made of liquid basalt (if those lodge in a wound, the enemy starts melting, and it's
glorious)
Hope it can be of use to you!
Place this one in the creature_standard raw:
[CREATURE:CROCODILE_MAGMA]
[DESCRIPTION:A huge reptile with thick black scales and amber eyes. It lives in magma rivers and it's able to spit out burning globs of basalt.]
[NAME:magma crocodile:magma crocodiles:magma crocodile]
[CASTE_NAME:magma crocodile:magma crocodiles:magma crocodile]
[CHILD:3][GENERAL_CHILD_NAME:magma crocodile hatchling:magma crocodile hatchlings]
[CREATURE_TILE:'C'][COLOR:0:0:1]
[PETVALUE:850]
[PET_EXOTIC]
[MOUNT_EXOTIC]
[AMPHIBIOUS]
[FIREIMMUNE]
[MAGMA_VISION]
[BIOME:SUBTERRANEAN_LAVA]
[UNDERGROUND_DEPTH:3:5]
[LARGE_ROAMING][DIFFICULTY:3]
[POPULATION_NUMBER:10:20]
[CARNIVORE][NATURAL]
[LARGE_PREDATOR]
[GRASSTRAMPLE:20]
[PREFSTRING:strength]
[BUILDINGDESTROYER:1]
[BODY:QUADRUPED:TAIL:2EYES:NOSE:2LUNGS:HEART:GUTS:ORGANS:THROAT:NECK:SPINE:BRAIN:SKULL:4TOES_FQ:4TOES_RQ:MOUTH:GENERIC_TEETH:RIBCAGE]
[BODY_DETAIL_PLAN:STANDARD_MATERIALS]
[REMOVE_MATERIAL:SKIN]
[REMOVE_MATERIAL:LEATHER]
[REMOVE_MATERIAL:HAIR]
[USE_MATERIAL_TEMPLATE:SCALE:STONE_TEMPLATE]
[BODY_DETAIL_PLAN:STANDARD_TISSUES]
[REMOVE_TISSUE:SKIN]
[REMOVE_TISSUE:HAIR]
[USE_TISSUE_TEMPLATE:SCALE:BASALT_TEMPLATE]
[BODY_DETAIL_PLAN:VERTEBRATE_TISSUE_LAYERS:SCALE:FAT:MUSCLE:BONE:CARTILAGE]
[USE_MATERIAL_TEMPLATE:CLAW:NAIL_TEMPLATE]
[USE_TISSUE_TEMPLATE:CLAW:CLAW_TEMPLATE]
[TISSUE_LAYER:BY_CATEGORY:TOE:CLAW:FRONT]
[SELECT_TISSUE_LAYER:HEART:BY_CATEGORY:HEART]
[PLUS_TISSUE_LAYER:SCALE:BY_CATEGORY:THROAT]
[TL_MAJOR_ARTERIES]
[BODY_DETAIL_PLAN:STANDARD_HEAD_POSITIONS]
[BODY_DETAIL_PLAN:HUMANOID_RIBCAGE_POSITIONS]
[USE_MATERIAL_TEMPLATE:SINEW:SINEW_TEMPLATE]
[TENDONS:LOCAL_CREATURE_MAT:SINEW:200]
[LIGAMENTS:LOCAL_CREATURE_MAT:SINEW:200]
[HAS_NERVES]
[USE_MATERIAL_TEMPLATE:BLOOD:BLOOD_TEMPLATE]
[BLOOD:LOCAL_CREATURE_MAT:BLOOD:LIQUID]
[CREATURE_CLASS:GENERAL_POISON]
[GETS_WOUND_INFECTIONS]
[GETS_INFECTIONS_FROM_ROT]
[USE_MATERIAL_TEMPLATE:PUS:PUS_TEMPLATE]
[PUS:LOCAL_CREATURE_MAT:PUS:LIQUID]
[BODY_SIZE:0:0:70000]
[BODY_SIZE:1:0:400000]
[BODY_SIZE:2:0:700000]
[BODY_APPEARANCE_MODIFIER:LENGTH:90:95:98:100:102:105:110]
[BODY_APPEARANCE_MODIFIER:HEIGHT:90:95:98:100:102:105:110]
[BODY_APPEARANCE_MODIFIER:BROADNESS:90:95:98:100:102:105:110]
[MAXAGE:60:100]
[ATTACK:BITE:CHILD_BODYPART_GROUP:BY_CATEGORY:HEAD:BY_CATEGORY:TOOTH]
[ATTACK_SKILL:BITE]
[ATTACK_VERB:bite:bites]
[ATTACK_CONTACT_PERC:100]
[ATTACK_PENETRATION_PERC:100]
[ATTACK_FLAG_EDGE]
[ATTACK_PRIORITY:MAIN]
[ATTACK_FLAG_CANLATCH]
[MATERIAL_BREATH_ATTACK:INORGANIC:BASALT:LIQUID_GLOB]
[ALL_ACTIVE]
[HOMEOTHERM:12000]
[SWIMS_INNATE][SWIM_SPEED:2500]
[CASTE:FEMALE]
[FEMALE]
[CASTE:MALE]
[MALE]
[SELECT_CASTE:ALL]
[SET_TL_GROUP:BY_CATEGORY:ALL:SCALE]
[TL_COLOR_MODIFIER:BLACK:1]
[TLCM_NOUN:scales:PLURAL]
[SET_TL_GROUP:BY_CATEGORY:EYE:EYE]
[TL_COLOR_MODIFIER:AMBER:1]
[TLCM_NOUN:eyes:PLURAL]
[SELECT_MATERIAL:ALL]
[MULTIPLY_VALUE:5]
[IF_EXISTS_SET_HEATDAM_POINT:13000]
[IF_EXISTS_SET_IGNITE_POINT:13000]
[IF_EXISTS_SET_MELTING_POINT:13000]
[IF_EXISTS_SET_BOILING_POINT:15000]
Place this one in the tissue_template_default raw:
[TISSUE_TEMPLATE:BASALT_TEMPLATE]
[TISSUE_NAME:basalt scales:STP]
[TISSUE_MATERIAL:INORGANIC:BASALT]
[RELATIVE_THICKNESS:3]
[HEALING_RATE:100]
[VASCULAR:1]
[CONNECTS]
[TISSUE_SHAPE:SCALES]