This tile, when placed on the floor of your base in the Sinnoh Underground in Diamond, Pear & Platinum, will send out a message informing the present users that the user is going to the Union Room when stepped on
Stepping on this Tool tells all nearby that you are going to the Union Room.
Episode #925 Ash-Greninja VS Mega Abomasnow! The Giant Water Shuriken Triggers!!