let pacManVisible options lineOfSight =
        let creaturesInDirection (directionVector: (TileContent * Creature list) list ) = directionVector |> List.collect snd
        let containsPacMan (creatures: Creature list) = match List.tryFind (fun c -> match c with
                                                                                     | int -> true
                                                                                     | _ -> false) creatures with
                                                        | Some value -> true
                                                        | None -> false

        if(Set.contains Up options && lineOfSight.Up |> creaturesInDirection |> containsPacMan) then Some Up
        else if(Set.contains Left options && lineOfSight.Left |> creaturesInDirection |> containsPacMan) then Some Left
        else if(Set.contains Down options && lineOfSight.Down |> creaturesInDirection |> containsPacMan) then Some Down
        else if(Set.contains Right options && lineOfSight.Right |> creaturesInDirection |> containsPacMan) then Some Right
        else None

    let decision (current: Move) (lineOfSight: Sight) (choices: Move Set) =
        let restricted =
            choices
            |> Set.filter (fun c -> not (c = backwards current))
        let options = if (restricted |> Set.count > 0)
                      then restricted
                      else choices
        let pacDirection = pacManVisible options lineOfSight
        match pacDirection with
              | Some move -> move
              | None -> randomMove options