Check out the old Bunkium and Truewall composites. Those are as close as you get to invulnerable, without using Wall.
Pressure bombs banned? Like doesn't literally every bomb use/create pressure in TPT.
a large glob of SING can break this armour with ease
ArtificialMushrooms: can you make a indestructible material
can you make a unbreakable thing for me
Soon you're going to have to ban the entire thing. I'm going to find ways around it.
it's supposed to be impossible