Added microtransactions into Terraria.
Okay, I looked up “undertale sans battle theme on flute”SMG4 (The Meme Lord).
Defence: 65,536 (the only way to kill him is using a Broken Wooden Hammer).
Atk. 1: Fires weird memes (and throwing World Destructive indestructible Nokia 3310 phones, despite being less-weird memes).
Atk. 2: summons his characters (like Meggy [an orange Inkling Girl, speaks in Spatoon's fonts], Dumb Mario [Mario, except way dumber and having crossed eyes, talks with the Super Mario 286 font], Waluigi [who attacks with an 10000x dmg Amethyst Staff and possesses everyone, same font as Mario], etc).
Music: crappy Undertale Sans battle theme on a flute.
Drops: 999999999999999999 platinum.
Summon: appears in Post-Moon Lord Blood Moons on the U R DED, NOT BIG SOUP RICE mode (You have a time limit, usually 25-30 minutes, to finish the game or you are eliminated, when you die, a voice clip of Team Fortress 2 Heavy saying "You are DEAD, not Big Surprise!" plays, [all of] your characters and worlds are deleted, your computer/handheld [as in Tablets and Mobile Phones, there aren't PDA's running Terraria]/console [Playstation 3/4/vita, Xbox 360/One, Wii U, 3DS, Upcoming Switch Edition] blows up, etc).