because obsidian qualifies as glass and it’s very sharp
Bro, what if the shadow crystals are flint. and the eggs will eventually be ground up, and mixed with metal. We have obsidian, flint, and steel. CHAPTER SEVEN IS OFFICIALY (I cant spell) TAKING PLACE IN THE NETHER
also my user is perfect for this comment
MINECRAFT LMAOOOOOO 
Obsidian is brittle though. Doesn't sound like a good material to make a sword out of. You may as well make it out of regular glass.
Oh wait, the Twisted Sword is in fact made out of regular glass. Okay nevermind, your theory still has legs.
but what if the obsidian is reinforced or smth
and plus, weapons don’t break in deltarune
L M A O
Counterpoint: The Knight's sword gets chipped. It's likely weapons can break, but it'd be really inconvenient, so it doesn't happen to our weapons.
what if its just, like, a magic crystal?
It seems to also be a glassy black shard in the light world, so it wouldn't make sense to be a magic crystal
Obsidian, being a glassy back substance, makes the most sense.
yeah, like in the dark world. What if it has the same properties in both worlds, like shadow crystals (or eggs I guess)
but the point is
weapons are absurdly durable in deltarune
nahhh bro
Actually, the black shard might be the only weapon that can reasonably be broken, since obsidian is insanely fragile.
If they are we need atleast 10 of them to go to the nether
Yes
we circled back to minecraft