Are you not aware they have an album prior to that? It's called Realms. It's a bit more ethereal and lacking more of the heavy elements that are found on Death Spells and Dimensional Bleed. Make sure you check it out! Foal has one of the catchiest guitar hooks ever.
I mean, like others have said - there's 3 full-lengths and an EP, so it's not a lot.
Realms - more post-rock/indie-ambient-gaze style, lacking a lot of the the heavier elements found later but absolutely fucking amazing. "Foal" is my favorite song.
Death Spells - classic album, heavy, moody, gazey.... 10/10, just a titan. "Yawning" is my favorite song.
Dimensional Bleed - good album, a bit more moody, kind of like Deafheaven turning more shoegaze with Infinite Granite. Still a great album, but nothing will ever top Death Spells IMO. That was a hammer to the face of the scene when that dropped.
The Black Moon - short, but crushing. Candy is a live set staple.
Just dive in dude, they're so good. I've seen them... 6 times now, soon to be 7 with Post Fest in a few weeks. They're so good, and so good live, and such nice dudes. Ryan is a sweetheart. He wrote a custom lyric sheet for me for my girlfriend, with the lyrics to "Take Me With You".
And those motherfuckers kept Yawning in the setlits! Sneaky bastards! I lost my shit in Boston and Austin just LOL'd onstage haha. It was great. Such good people.