Mildly important information not mentioned by the Wiki

Skeletron despawns if you Recall away from the dungeon.

You see, I didn't want to make a whole ass one-or-two-use arena outside the dungeon, so instead I decided to buff up, summon Skeletron, and recall to spawn and fight him in the arena there. I even checked the wiki to make sure that he wouldn't despawn, and it said nothing about it. Queen Bee didn't despawn when I accidentally recalled, instead she enraged as I rushed back to the jungle.

Basically I'm just salty about wasting my potions. I knew there was a chance of it not working, as I had never seen anyone fight Skeletron anywhere but by the dungeon, but I thought I would be smart and play by my terms. Did not work.