Make me build a Minecraft minigame.

[FizzletheMovieTheater]

Much like my other thread (don't be mad at me, mods), I need minigame ideas! Boss me around with them below, with a name, how it works, and any extra 'lil details I should add. Thanks, and God bless.

 

[Anglefish]

How about a minigame where you create a giant cave and hide a specific number of diamonds throughout it? After a player picks up a diamond, they can't drop it and they earn a point. The player with the most diamonds at the end wins.