How have you never heard of it?
It's always pretty high in best of metroidvania lists. Combat is projectile based like the old Metroid games, so no melee like most metroidvanias.
I played Blasphemous a couple of months ago. Lovely artwork and I generally enjoyed it, but not among the better ones in my opinion. Here's a couple others I played in the last few weeks:
- Iconoclasts: this is often listed as a metroidvania but it's more of a 2d action/puzzle platformer that's very story heavy. Lots of character dialogue. Very colourful pixel art. An unusual game, it's interesting but gets old well before it finishes. Probably not the best choice if you're looking for a metroidvania
- Momodora: Reverie under the Moonlight. A very short metroidvania. Despite intially releasing in 2016, it feels old, with its low res pixel art and 4x3 aspect ratio (yes, seriously, you will have black bars on the sides). I liked the art style though, it gives it a very moody atmosphere. Enemies and bosses are pretty cool, if not very challenging on normal. If you're looking for a cheap and short experience, you could do worse than this one.