Inspired by BastiGHG
When the battle starts you will see the name of an item on the top of your screen (in the bosssbar). Now your goal is to get this item as fast as possible. On the bottom of your screen you can see a timer ticking down. If the countdown reaches 0 the battle is over and the player who got the most items wins.
To help you if an item is too hard to get you have (by default) 5 jokers. Use them to get the item your currently having to get. But use them wisely...
Just put this plugin in your plugins folder and everything will work.
Images:
Start:
If you are op you will have a start item in your hotbar. Right click with it to start the battle
or type "/start" in chat (without quotes) and the battle will start.
If you want to change the time of the battle or the amount of jokers just change it in the config,
or type "/start [countdown_time] [jokers]" in chat. Replace [countdown_time] and [jokers] with numbers you want to have.
Goal:
Get as many points as possible by collecting as much items as you can. Good luck!
Settings
If you are op you will get a command_block_minecart in your hotbar. By right clicking with it you will open the settings inventory. Here you can change and set all important settings.
If a setting is true the item will be enchanted to let you get a quick overview of your current settings.
Settings are (from top-left to bottom-right):
Teams
set if you want to play in teams or everyone on their own
Difficulty
change the difficulty of your items to get
Start
a button to start the game from inside this inventory
Damage
if the players can get damage or not
PVP
if pvp is allowed or not
KeepInventory
if keepinventory is true or not
Change walking speed
if you want to change everyones walking speed
Fly
allow or deny everyone to fly (even in survival)
Give players haste effect
if all players should get a permanent haste effect
Give players jump boost effect
if all players should get a permanent jump boost effect
WalkingSpeed (just available if change walking speed is true)
set how much faster or slower the players can move
FlySpeed (just available if fly is true)
set how much faster or slower the players can fly
HasteLevel (just available if haste is true)
set the level of haste the players should get
JumpBoostLevel (just available if jump boost is true)
set the level of jump boost the players should get
Commands:
/settings
opens an inventory with some settings to play around with
/start [countdown_time] [jokers]
starts the battle with the given settings
/stoptimer
stops the timer
/skip <player_name>
skips the current item of an player (incase it is too hard)
/reset
generates a new world for a new battle
/top
teleports the player to the surface. If used in the Nether the player will get teleported to the world spawn
/bp
opens your teams backpack
/invsee <player_name / team_name>
will show you the inventory of the given player. You can also take or deposit items from it
/teleporter
opens the teleporter inventory. There you can teleport to every online player in survival mode by clicking on their head
Permissions:
If you need the permissions of the commands please look at my GitHub page in the provided source code.
Future plans:
✓ (DONE in V2.0) A multiplayer mode is in process, so that you can play together in teams with your friends. Then you will work in teams together to get the items even faster.
If you made it this far, please consider rating my plugin! 
Don't forget to check out my other plugins:
https://www.spigotmc.org/resources/authors/170.1502863/
Inspired by BastiGHGs video on this battle: