Chain

Placed chains climb exactly like rope, at the same pace up and down, with one difference that decides how you use them: they cannot be rolled into a coil and thrown down a shaft. That makes them a building material you place deliberately rather than a caving tool you deploy on the fly. Placed chain also counts as background decoration, so a wall of it will not satisfy the wall requirement for a house, will not make a room valid for an NPC, and cannot be actuated.

Most of the early quality of life recipes want chain: the grappling hook, the sawmill, every tier of watch, heart lanterns and the entire chandelier family. A single bar produces a pile of them, so there is no reason to craft them one recipe at a time. Chain also survives lava in both placed and dropped form, which is unusual enough to matter when you are building platforms over the underworld and dropping things by accident.