That was a really long intro, interesting! It definitely helps set up atmosphere and the rest of this hectic track. I think my favorite thing about your piece is the progression, as it starts as this one thing, and in the middle it's almost something completely different, but yet the song flows perfectly. Nothing too spontaneous, everything feels like it fits. Also love the synths that come in around 02:15, very creative use of them! If anything a lot of the sounds you use in your piece here are very cool. Overall I think this is a very unique boss theme approach, it sounds very trailery even, and I think you'll find lots of success making more of these tracks ;)