Water Breathing. The opabinia can breathe only underwater.   Collecc Weapon. The opabinia can replace an attack with a Strength (Athletics) or Dexterity (Sleight of Hand) check contested by the target's check. On a success, the opabinia can disarm the target of a weapon it is holding. If the weapon does not have the heavy or two-handed properties, the opabinia can pick it up as a bonus action using its proboscis, and use it to make attacks on subsequent turns. While wielding a weapon, the opabinia cannot use its snibbety snab attack.