Hammer doesn't break adjacent Astral Sorcery marble blocks in 1.15.2.

[AnotherVagabond]

For some reason, the hammer doesn't seem to be treating Astral Sorcery's marble blocks as stone blocks when checking to break adjacent blocks. I tried both with breaking a marble block, which mines the target block normally but no adjacent blocks, and with breaking a stone block next to marble blocks, which broke the adjacent stone blocks but not the marble ones. This is from the latest files for everything in 1.15.2 (sorry I already deleted the modpack since I was done testing the stuff I was testing, so I can't grab the specific version numbers).

Edit: Oh, I also tried with the marble bricks and pillars (I was at one of the small shrines) and it didn't work with any of them.

[noobanidus]

That implies they have a different harvest level...

[AnotherVagabond]

They drop their block just fine, though, and harvesting a marble block should still harvest the ones around it since those would all be the same harvest level, right? I'm not sure if a block can have a harvest level but still let you harvest it without a high enough level tool.