Cockatrice

You may mean Spirit cockatrice or Chocatrice.

Cockatrice are Slayer monsters that require level 25 slayer to kill. They frequently drop Limpwurt roots used in the Herblore skill. Players need to use a mirror shield when fighting these.

Locations

 * Fremennik Slayer Dungeon

Strengths and weaknesses
Players must use a mirror shield when fighting these. If a regular shield or no shield at all is equipped the cockatrice will shoot out beams from its eyes and quickly reduce a player's stats to dangerously low levels and rapidly hit 9's. They have few hitpoints and do not hit particularly hard unless the player forgets the mirror shield.

100% Drop
Bones

Other

 * Coins (1, 5, 15, 28, or 62)
 * Level 2 Clue Scroll
 * Limpwurt root (very common)
 * Cockatrice head (rare)
 * Half of a key
 * Cockatrice egg (common)
 * Chaos talisman

Gems

 * Uncut Sapphire
 * Uncut Emerald
 * Uncut Ruby
 * Diamond

Runes

 * 3 Law runes
 * 2, 4, or 6 Nature runes
 * 2 Water runes
 * 7 Fire runes

Weapons/Armour

 * Iron javelin
 * Steel dagger
 * Iron sword (common)
 * Steel longsword
 * Iron boots
 * Mystic boots (uncommon)
 * 5 Rune Javelins (rare)
 * Dragon Spear (very rare)

Summoning Charms

 * Gold charm
 * Green charm (common)
 * Crimson charm
 * Blue charm

Herbs

 * Guam
 * Marrentill
 * Harralander
 * Tarromin
 * Irit
 * Avantoe
 * Kwuarm
 * Dwarf Weed
 * Ranarr
 * Lantadyme
 * Cadantine

Seeds

 * Potato
 * Onion
 * Cabbage
 * Strawberry