Terraria Calamity is a Terraria mod that adds loads of bosses (they are all super cool except THAT one...), biomes (i hate the abyss it can go #!%^#*%^), weapons (funny magic gunk saxophone go brrr), and more other random fun stuff. I have been playing it practically nonstop with one of my friends and we have gotten to post-golem as of february 10th
Song playing is Terraria's Deerclops theme Yes, Deerclops is from Don't Starve Together but like... the song is so good and they did crossover :)