Hi Josh! Without a doubt, this is one of the most difficult questions I can answer because there are so many openings that I like.
But, here are some of the openings I love the most: Departure! by Masatoshi Ono (Hunter x Hunter)
Brand New World by D-51 (One Piece)
Silhouette by Kana-Boon (Naruto)
Ranbu No Melody by SID (Bleach)
What's Up, People?! by MAXIMUM THE HORMONE (Death Note)
A Cruel Angel's Thesis by Yoko Takahashi (Neon Genesis Evangelion)
Jiyuu No Tsubasa by Linked Horizon (Shingeki No Kyojin)
Howling by Flow (Japan) & GRANRODEO (Nanatsu No Taizai)
Little☆Date by Ribbon (Ranma 1/2)
Kaikai Kitan by Eve (Jujutsu Kaisen)
... View more