While digging through the files of Wario Land 4, I found a file internally named “redjaybird.boss”. While looking through it, it would supposedly be the boss of an unused “Nest Passage”. The boss itself is literally Red from Angry Birds. What’s weird is that this game out 8 years before the original release of Angry Birds. The boss would just sit there, not doing anything but looping its idle animation, as this is unfinished. The boss takes only 1 hit. Neither Nintendo nor Rovio confirmed that this was a planned boss, but it would’ve been a really cool boss if it were finished and in the full game.
Nintendo Rovio @Danny-remakes for the Red vector I used in the background