Blue Twilight DX is a non-profit unofficial fangame based on the Mario universe. It combines elements from 3D Mario titles with classic, 2D gameplay, set in Halloween-themed levels. The original game, Super Mario: Blue Twilight (MarioWeen for short) was developed in the span of two short weeks and released on October 31st, 2003. MarioWeen DX was slated for an October 31st, 2004 release, but what was once a small upgrade (an extra level and an extra boss) quickly snowballed to a much larger game that pushes the clunky little game to it's limits. Features:

- 7 levels, plus 4 hidden levels
- 4 bosses, plus 2 hidden bosses
- Concept Art, Scrapped Levels
- Text-based Director's Commentary
- Plenty of easter eggs
- Revised level designs over the original game
- Date activated secrets
- Playable Luigi