Trial Key Opens Up Trial Chamber Boss Room or Loot Chest (Slider Boss Idea)

I'm sure Mojang already has a wonderful idea cooked up for the Trial Key item that can be found in the brand new Trial Chamber structure. However, I was recently playing the Aether mod ((A phenomenal mod that I'm sure needs no introduction here, hi kingbdogz and team!)) an idea came up the form of a possible new Minecraft boss inspired by the Aether Slider boss / and or possible use for the key (which could be used to open up an unbreakable loot chest or could be used to open up doors which lead to the boss chamber that houses the Slider mob itself.) 

The Slider for those unaware, was the third boss found only in the Aether dimension, usually residing in Labyrinth dungeon types, a "trial chamber" like structure filled with deadly mobs and traps. These boss mobs could only be damaged by attacking them with pickaxes and would speed up the more damage they took. For attacks, these bosses would attack the player by sliding around the room and throwing players upward upon touching them, along with 8 hearts of health taken from the player per hit.

Upon defeat, would drop a bronze key that could be used to open up a hidden boss loot chest which would only reveal itself upon defeating the boss. Perhaps the keys we see inside the Trial Chambers could be used to open a special type of door to the locked boss room which holds the new Copper Slider boss, or it could be used to open up a special copper chest found only upon defeating the boss/chamber structure itself for the first time.