This may be our console because it needs to update and our wifi doesn't do updates, but the Hallow suddenly began to lag just today. Our console is not connected to the Internet. Both me and my little brother have experienced it. I was chilling in the Underground Hallow in my new playthrough, mining, killing for souls, that kind of stuff, and I was fighting a Chaos Elemental (using a Fiery Greatsword because the transition into Hardmode is what always gets me but I'm doing good so far) and, out of nowhere, LAAAAAAG. The HUD continuously dissapeared and reappeared, the game repeatedly froze and unfroze, that kind of stuff. It doesn't lag in my surface forest spawn, but it does lag in my little brother's surface hallow spawn, so I'm pretty sure it's either our console or the Hallow.