Lacrimis

 The tears that fall from crying obsidian have a surprising amount of magical power.

and Patchouli

To start, a guide for these powers can be found by using a book on the block in question. From there, line a caldron with gold and do some experiments. This guide book, the ingame recipe book, and many advancements are arranged to lead you forwards.

Create large rune arrays that can teleport, move blocks, and edit mob spawners.

Build invulnerable walls out of magical power.

Discover a new way to defy death, and the unique benefits it brings.

All from the tears that collect in a crucible.

Helpful tip: if you are running low, more crying obsidian can be found in the end pillars.