Commands/achievement

Gives or takes an achievement from a player.

Arguments

 * name
 * Specifies which achievement to modify. Must be one of the following:
 * , where achievement_name is a valid achievement identifier.
 * represents all achievements.
 * player (optional)
 * Must be a player name or a target selector. If not specified, defaults to the command's executor. Not optional in command blocks.

Result
Fails if the arguments aren't specified correctly, or if  fails to resolve to one or more online players.

On success, grants or removes the specified achievement(s) (and all prerequisite achievements) to the player(s).

Examples

 * To grant the "Overkill" achievement to oneself:
 * To grant the "Taking Inventory" achievement to Steve:
 * To remove all achievements from all players: