Xultris is a variant of the computer game classic Tetris, in which you have to fit falling bricks together to win points.

It is designed exclusively for use with Mozilla, the open-source browser from Netscape, although it will also work with NN6 and other variants. This also means that Xultris will run on any platform that will run Mozilla.

The user interface has been designed using Mozilla's Cross-Platform Front End (XPFE), and uses the XML User-Interface language (or XUL - hence the name Xultris) and Javascript to create the front end.