My opening point is that Solar Wind by Jumper is an incredible song and works well in literally every level it's ever been used in. Sol Invictus (or Invincible Sun from Roman, this doesn't matter at all but it's cute) very clearly does not cohere to modern conventions, strangely drawing influence from many updates prior to 2.2. Many of these were probably never considered in the creation process, but it was fun to think about for myself anyway. The designs themselves are mostly one or two block palettes, like many old (~1.9ish) levels did before compound block design was really required to not look silly in a high quality project. Similarly, the structuring is noticeably old fashioned and strangely seems to go back even further than the 1.9 era, calling back levels like B L A Z E and pretty much anything that was popular in 1.8. The gameplay is inexplicably very 2.1 coded, almost seeming hesitant to be more complicated, but the clearest parallel I can pull to older styles are the faded structures in the background, very reminiscent of some early forms of custom backgrounds and a desire to fill space as it was a growing convention. These structures are probably my favorite part of the level, especially with the way they're all a little rotated and often move to balance out much of the foreground being annoyingly static. The color work is also pretty good; I'd wish for either the whole level to be orange or change throughout the level and not just towards the end, but the compromise is fine enough. If I had to sum up my issues with this level it just feels boring, and not just because of some lackluster designs. Despite the song picking up speed, the second half doesn't play all that differently from the slower parts, and the duals actually slow it down further which feels entirely wrong to me. I do enjoy early 2.1 gameplay a good chunk of the time, but I also made the comparison to say that it's really not that exciting most of the time, including in Sol Invictus. The colors and designs also don't do much in terms of progression, I'm fine with a visually consistent level but having a more colorful and flashy drop could have picked up some of the slack the gameplay left. Overall, though, Sol Invictus is a perfectly fine and fun level that I hope Metronismo's happy with.