The Tadpole Pens access is gated by a keycode, and the usual way to get it is to press the red button at the locked door first, then follow the ping to Zip’s Black Box in the Hot Caves southwest of the Pens. One guide places the Pens about 675 meters east of the Lifepod, and says the Black Box is in a deeper cave area reached by heading southwest and descending into the geothermal zone.

What to do

  1. Go to the Tadpole Pens and enter the facility.
  1. Find the locked door and press the red button to trigger the next objective.
  1. Follow the Black Box location marker to the Hot Caves area southwest of the Pens.
  1. Retrieve Zip’s Black Box/keycode, then return and open the door.

Route notes

  • One guide says to stay near the ocean floor and head southwest from the Pens to find a hole in the seafloor, then descend deeper until you reach the Black Box.
  • Another walkthrough says you may need to keep moving through the cave system until you reach the purple growth with the hologram marker, where the Black Box is located.
  • Some guides also mention needing the right progression or gear to survive the hot zone safely before reaching the objective.

Quick tip

If the door still says you need authority, it usually means you haven’t scanned or activated the Black Box objective yet, or you’re missing the keycode step from the pinged location.

TL;DR: enter the Tadpole Pens, press the red button, go southwest into the Hot Caves for Zip’s Black Box, then come back and unlock the door.