The Trials series is known for its 'easter eggs'. Actually 'easter eggs' is underselling it somewhat. Trials HD had a riddle and Trials Evolution had a riddle so insane it can't be solved this century.
Now Trials Fusion is playing host to some seriously weird shit.
But as awesome as this little easter egg is, it's blatantly not part of a broader Trials Fusion riddle. At this point I'm starting to wonder if there actually is a Trials Fusion riddle. But seriously, how can Red Lynx top the last one?
If you want to stay in the loop regarding this kind of weird stuff, your best bet is a YouTube subscription to Professor FatShady. He tends to stay on top of this stuff.