Midnight Horrors provides a Bestiary that was added in Version 1.52.0. The bestiary shows Bosses you have fought in the past and information of that specific Boss. The info will only be shown if the player has won against that Boss/MiniBoss.
"*hey kid, surprised you still play this game after all of this time. anyways, thanks for putting up with me that one april fools."
(2020): "Lo and behold he's back, as a sinister, Death is merely a minor hurdle until he finds himself a way to regrow his body from the soil. This time however, you're here on Jack's orders."
(2022): "Lo and behold he's back (again), having taken over Roblox HQ by taking advantage of the Burrito Incident Hallow has turned its servers into his very own simulation device. Now its your turn to overthrow this power-hungry Server Moderator because in all honesty he's just not ready for the task.
"A rotten corpse of a rotten man wielding a powerful scepter that harnesses the power of the sun. It was by his hands Oculus found earth long long ago."
(2020): "Having foreseen your arrival, Jack Frost created this fake puppet body to keep you busy, not wanting to deal with your meddling. Alas however, it seems you've bested this mere temporary replacement. No matter, where he actually resided remained a mystery."
(2022): "The embodiment of all that is cold, Jack Frost's heart is just as bitter as the frozen breeze of a cold christmas night. You dare attempt to take him on? You dare attempt to stop him? What good does your gear do you, if you can't even inflict a single wound. Now, begone from his castle!"
"Four Fiendish Fakes stand before you here in... Ikea? Oh, who cares. What does matter is the fact that they stand before you and... Your purchases? In all honesty, god knows why you fought them then and there."
"Hound, Hellraiser, and Hailstorm. Three of the five most powerful mechanic creations of Oculus. Here, they stand before you to aid their steel allies in battle. And more importantly, they don't plan to go down without a fight."
"NOTICE ALL RECRUITS! WE HAVE A LARGE SCALE MECHANIC THREAT INBOUND! SET OUT AND GET YOUR FISTS DIRTY! And while you're at it... Please, don't bother waking up, you're just too interesting."
"The spiritual successor of the EGG9000, this mechanical mastermind was put in charge of some non-distinct laboratory. Alas, misguided by his own hubris he wiped the place clean of all human life. Now he sits alone, pirating Movies and watching YouTube all day."
"Play NieR ~Joel, probably"
"Sweden, reduced to a wasteland of Joels. And the Netherlands, fighting an infinite war with the aquatic kin. These two warriors represent their entire landmasses, why? Who cares!"
"A native from Canada, thought not it's representative. They are responsible for ferrying the deceased to their land, where most of their kind thrive from it. The method of what kind of Goober one becomes from his process is unknown."
"The perfect thanksgiving meal and every way possible, but being having such a perfect meal doesn't come for free, it won't give you the honor of eating it unless you manage to best it in the ring of honor. It may have a pitchfork but it never uses it, it doesn't need it he'll take you down with his bare hands alone. Only the strongest get to wield his fork and taste his flesh."
"You did quite a number on him back at Jack's place, you know? Twice no less. well, he won't stand for it. With crushed pride you challenge him a third time, this time however things are different."
"Hatred. Sorrow. Fear. Powerful emotions possessed by the most living things just like you, just like they. But the sins committed against them cannot allow them to let go of these emotions... Possessing what little there is, you square off against the past."
"The Cardinal Dietes and their creator have the power the bestow the title of Chosen One upon any individual of their choosing, those with this title are given immense power far beyond what is normal for their kin. When two Chosen Ones square off however they cancel one another out. That's probably the only reason you still stand today.
"A newborn, created just moments before your encounter. Formed solely through the rage of the Vengeful Spirits inhabiting that old dusty dungeon this beast and those like it will stop at nothing until their rage is quenched, everything up until now was a clash of ideals and morals, underlined by the chance of divine intervention. This time, the both of you fight to the death, for the right to leave this arena and step back out into the world. Sadly for it, now that you've struck it down it cannot rest, for its consciousness will rot away in that same spot, forever."