Fidget
The Destroyer
As it is right now, whenever you enter a building in Terraria, your pet lags just far enough behind you that they get stuck outside when you close the door. This leads to them bouncing up and down unless you walk far away enough to make them phase through the wall. It's a nitpick, but this drives me utterly insane and I usually just turn pets off because of it. I think a simple change would be to allow pets to open and close doors or simply phase through them, following the player at a closer distance.