Orca

Orcas are only on the console and mobile. They are only harder versions of Sharks and are found in Oceans.

Tips

 * Orcas charge the player and can move quicker than most players. They are highly resistant to knockback, but strong weapons will usually at least halt their advance.
 * Rapid-fire weapons and flails tend to be effective. The Trident is highly effective, as it will always hit three times as it passes through the Orca.
 * Using a Water Walking Potion to stand at the surface and dive slightly down periodically, you can attract Orcas to within striking distance while staying safe. The Flipper accessory will keep you from sinking to the bottom.
 * Construct a spot to stand on, but remain half-inside water. Add a shield of blocks in front of you to one tile above the water's surface. Use an arcing ranged or Flamelash-type weapon to fire around the shield, or a Vilethorn to fire through the shield.
 * A similar method is to stay on the Ocean floor, dig a small pit in the sand, and build a shield above you but not connected to the ground, leaving a one-tile gap. Orcas will try to attack but won't fit. You can then attack with impunity. Lacking proper swim gear or Neptune's Shell, a stack of Gills Potions may come in handy for this approach.
 * If you have flippers and a ranged weapon, you can go faster upward than the orca, resulting in killing it.

Trivia

 * Orcas hardly ever attack humans in real life.