variables: {event} = false  
on mine of stone: 
    if {event} is set: 
        chance of 10%: 
            if player can hold 1 stone: 
            give 1 cobblestone named "bruk" with lore "Material wybuchowy" to player 
        else: 
            drop 1 cobblestone named "bruk" with lore "Material Wybuchowy" at player 
command /eventbruk: 
    trigger: 
        if player has permission "event.admin": 
            if {event} is not set: 
                set {event} to 1 send "&aWlaczyles event!" 
                stop 
            if {event} is set: delete {event} 
                send "&cWylaczyles event!" 
                stop