Heres my take on grians last life! completely made by me!
How to use:
First just download the datapack and put it in your datapack folder, then when you load or /reload the datapack in your world/server you should get a book with some options. The most important one are the first and second, the rest are just for debug/checking purposes.
Also for clarification, BM = BoogeyMan.
"Choose the boogeyman" when you click this, it sends a message to everyone saying the boogeyman is about to be chosen, after a couple seconds it will display a message counting down and will say if you're the boogeyman.
"give everyone random lives" Pretty straightforward, when you click this, it gives everyone random lives ranging between 2-6.
I havent implemented the "fail to kill and you turn red" part yet, so if you want to do that just do the command:
/scoreboard players set [name] Life 1
and obviously [name] is the name of the player who failed.
When a player reaches 0 lives, they will be put into spectator mode. For general rules of last life I recommend using the wiki: https://the-life-series.fandom.com/wiki/Last_Life