Stella posted a new challenge:

First, you need to read the letter in the order given by the dart numbers as shown here:

This should give you "TUVNLNXCIPHERKEYDART".

Vignere-Decoding "TUVNLNX" with the key "DART" gives the solution (see http://rumkin.com/tools/cipher/vigenere.php)

Solution redirects to:

http://www.ancientsocieties.com/hira-shuriken/