[Vero]

pawn Код:

command(mask, playerid, params[])
{
    if((g_fMask[playerid] = !g_fMask[playerid]))
    {
        for(new i = 0; i < MAX_PLAYERS; i++)
            ShowPlayerNameTagForPlayer(i, playerid, 0);
        SendClientMessage(playerid, PURPLE, "You have put on a mask." );
    } else {
        for(new i = 0; i < MAX_PLAYERS; i++)
            ShowPlayerNameTagForPlayer(i, playerid, 1);
        SendClientMessage(playerid, PURPLE, "You have taken the mask off." );
    }
    return 1;
}

Other bit of the script if it helps