Undersea Odyssey: Coral Reef Hunt

Nurro, Undersea Odyssey, coral reef, Eyewire, citizen science, marine biology

The next stop on our journey is much closer to the surface, in one of our oceans’ gorgeous, colorful coral reefs. You may think of coral reefs as primarily appearing in shallow, tropical water, which is true, but reefs do occasionally grow in deep water or closer to the Earth’s poles. Likewise, although they cover less than 0.1% of ocean area, they contain more than 25% of marine life! This life takes many forms you may recognize easily: sea urchins, sea horses, sponges, anemones, angelfish, clownfish, and so much more, but most of all… coral itself!

If you can believe it, coral is an animal, not a plant. Coral structures form from tiny individual polyps with tentacular mouths; they excrete material that forms an exoskeleton, which fuses polyps together. By this means, and through hundreds of millions of years of evolution, coral has grown into the reefs we know today, and it’s become a key ecosystem for biodiversity. For the next several days, Eyewire will have a coral reef of its very own, where some mergers are hidden among the branches; can you find them?

There are 12 mergers in the Hunt cell. You have 5.5 days and 24 guesses to locate them all, between midnight EST on 2/16 and noon EST on 2/21.

How to identify and report mergers

    1. Select Hunt cell from Change Cell menu. Stay in the overview.
    2. Type /debug into chat. This will reveal a special box with information about the cell (located above the “Start Playing” box).
    3. Use ALT+click to select the origin point of the merger you have identified. It is a good idea to zoom in close on the merger before you select it to get the most accurate coordinates.
    4. Find the coordinates of the merger’s origin in the cell information box. These are next to the word “center.”
    5. In the chat pm thehunt bot your coordinates. For example: /pm thehunt 5123 4321 5678.
    6. thehunt bot will let you know if you got it right or wrong and tell you how many guesses you have left.
    7. To check how many mergers you have found and to check what guesses you have submitted, type “/pm thehunt !list”; the bot will give you a list of all the coordinates you have guessed, and whether or not there was a merger at each set of coordinates. A + means there was a merger there, a means there was not a merger there.
    8. If you accidentally submit the same coordinate a second time, it does not count as two guesses.

Do not reveal your coordinates to other players. Do not do anything against the spirit of the Hunt. Anyone caught cheating will be automatically disqualified from the event and will not receive any points.

Proximity to merger start point is determined by number of voxels (1 voxel = approx. 1/250th of a cube’s width). Mergers are only counted as found if guessed within a distance of 250 voxels.

Swag (generously sponsored by @susi): The top scoring player will win 1 tote bag and 1 sticker sheet! Second and third place each also win sticker sheets.


  • 1000 points for each merger found
  • An additional 7500 points for anyone who locates all 12 mergers
  • 200 point bonus available on each merger to the player whose guess is closest
  • 250 point bonus available to any player who guesses within 10 voxels of a merger


It is unlikely, but in the event you find a merger HQ did not plant on the cell, please let us know. If we verify it, then we will award you 1000 points. If it is a merger on top of an intentionally added merger, then that will not count.

Pieces of dust floating in space don’t count as mergers, so don’t report them!

This is not a merger!


Artwork by Daniela Gamba