The #100DaysOfCode challenge is a 100-day coding marathon where participants commit to writing code for at least an hour each day. TwilioQuest, a video game, can help support this journey by providing interactive real-world services that allow players to write code and interact with APIs such as sending automated SMS messages or creating video apps. The game also covers essential topics like learning programming languages like Python and JavaScript, understanding Git and GitHub, and making open-source contributions. With its content and gameplay, TwilioQuest can help keep momentum going during the 100-day challenge, allowing participants to focus on their projects and improve their coding skills.