Xylia
Terrarian
LAN is great if you have multiple PCs, but given the age range of a lot of Terraria players (both siblings playing with each other, or parents playing with young children), a LAN setup may not only be technically imposing (due to lack of knowledge of how to do so for children or tech-unsavvy people) or impossible entirely (due to children not necessarily having dedicated PCs of their own.)
Imagine a parent with 2 children and a single PC in the household . . . multiplayer with each other is more or less out of their grasp.
Well, I suppose so... though if you have 2 kids in your household... you really ought to look into getting a computer for each because face it... you're going to have fights breaking out in a few years.