Enter command "/help Inv_Replacer" to get command help in Game.
The Plugin adds 5 command.

1 - headadd
You can use this command to place a block in player's head.
Grammer: headadd <Player> <Block>

2 - replace
You can use this command to replace an item in some-player's inverntory.
ItemNumber is means the position of Item 's Item grid in the inventory.
It's from left to right.1-9
Grammer: replace <Player> <ItemNumber> <Item>

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