Diamond (InstanceTopic, 5)
From Compile Worlds
For the Chao that User:Chao raised, see Diamønd.
Diamond is a really rare, valuable gem, and it is without a doubt the strongest substance that exists. It's top tier in Minecraft. You'd think the same would apply in Motherload, but they shoe-horned something called Amazonite in there to push it down to second place instead.