There's a song that plays in My Hero Academia season 2, episode 41 around 20:45-20:58ish when the villains showed up during the poison gas/tree burning scene. It was growling black metal type vocals and drums.
What is that song?
From what I can gather, the only artist mentioned in the end credits is Miwa. After hours of searching all I could come up with was this video of her doing a metal cover. https://www.youtube.com/watch?v=8eVHPqmgvrE It sounds close, but Im not 100% sold on it. But it does prove she can sing that style so perhaps its a new song by her. If that is the case we will have to wait for the OST.
It's call All out Attack on the MHA soundtrack.