every 1 tick:
    loop all players:
        if chestplate of loop-player is diamond chestplate named "ZBROJA" with lore "Sila: +10||Kondycja: 2":
            apply speed 2 to loop-player for 1 second
            if {zbroja.1::%loop-player%} is not set:
                set {zbroja.1::%loop-player%} to now               
        else:
            if {zbroja.1::%loop-player%} is set:
                clear {zbroja.1::%loop-player%}
                remove speed from loop-player
on damage:
    if {zbroja.1::%attacker%} is set:
        add 10 to damage
command /zbroja:
    permission: zbroja.admin
    trigger:
        add 1 of diamond chestplate named "ZBROJA" with lore "Sila: +10||Kondycja: 2" to player
        send "Otrzymales zbroje!"