Introducing "Dungeon Escape"; my answer to the Python Dungeon Challenge

"""
DUNGEON ESCAPE
==============
A tiny game meant to be enjoyed from the comfort of your
terminal. The idea is simple: the player is in a dungeon
and must escape from a monster by moving one step at a time
in any of the four directions until finding the exit door.
The player loses by moving into the same spot as the
monster, and wins by reaching the exit door.
"""


import os
import random
import sys

def clear_screen():
    if os.name == 'nt':
        os.system('cls')
    else:
        os.system('clear')

# Notify user of his/her location.
def print_coor(player):
    print("Your coordinates now are x: {}, y:"
              " {}.".format(player['x'], player['y']))

def print_help():
    print("Type a command to execute the desired action:\n"
          "'up' -> go up\n"
          "'down' -> go down\n"
          "'left' -> go left\n"
          "'right' -> go right\n"
          "'help' -> show help\n"
          "'quit' -> exit the game\n")

def exit_game():
    print("Exiting into the light...")
    sys.exit()

def play_again():
    try:
        user_response = input("Would you like to try your luck again? "
                              "Y/n\n> ").lower()
    except ValueError:
        print("What did you say? Y/n\n> ")
    else:
        if user_response == 'n':
            exit_game()
        else:
            play()

def print_map(x_axis, y_axis, player, player_traces):
    # Start by drawing the top of the map.
    map = "+" + ("---+" * max(x_axis)) + "\n"

    # Draw line by line. Since the origin is located
    # at the bottom left corner, use the reversed order
    # of the y axis.
    for y in reversed(y_axis):
        map += "|"

        # For each quadrant, draw a space and decide what
        # to fill it with depending on what's in there;
        # the player, a trace, or just empty space.
        for x in x_axis:
            if x == player['x'] and y == player['y']:
                fill = "X"
            elif (x, y) in player_traces:
                fill = "*"
            else:
                fill = " "
            map += " {} ".format(fill)
            if x == max(x_axis):
                map += "|\n"
            else:
                map += " "

        # Draw the decoration between lines.
        if y > min(y_axis):
            map += "+" + ("    " * (max(x_axis) - 1)) + "   +\n"

    # Finish it off by drawing the bottom of the map.
    map += "+" + ("---+" * max(x_axis))
    print(map)

def play():
    clear_screen()

    # Create a map of coordinates.
    x_axis = tuple(range(1, 11))
    y_axis = tuple(range(1, 11))

    # Put the player on the map.
    player = {'x': random.choice(x_axis), 'y': random.choice(y_axis)}

    # Create a trace the player will leave as he/she moves around.
    player_traces = []

    # Put the monster on the map while making sure it won't
    # appear in the same spot as the player.
    monster_spawn_area_x = list(x_axis)
    monster_spawn_area_x.remove(player['x'])
    monster_spawn_area_y = list(y_axis)
    monster_spawn_area_y.remove(player['y'])
    monster = {'x': random.choice(monster_spawn_area_x), 'y': random.choice(monster_spawn_area_y)}

    # Put the exit door, again making sure not to place it
    # in the same place as the player or the monster.
    door_spawn_area_x = monster_spawn_area_x
    door_spawn_area_x.remove(monster['x'])
    door_spawn_area_y = monster_spawn_area_y
    door_spawn_area_y.remove(monster['y'])
    door = {'x': random.choice(door_spawn_area_x), 'y': random.choice(door_spawn_area_y)}

    print("######################## DUNGEON "
          "ESCAPE #############################\n\n")            
    print("Welcome to 'Dungeon Escape': an adrenaline packed horror game "
          "back from a time when nobody knew what the hell a GUI was.\n\n"
          "Find your way out from the dungeon by moving one step at a time "
          "without being noticed by the evil monster lurking in the "
          "shadows. Good luck! "
          "You are gonna need it.\n\n")
    # Tell the user how to play the game from the very start.
    print_help()
    print("The dungeon's size is 10 by 10. You can move one step at a time.")
    print_coor(player)
    print_map(x_axis, y_axis, player, player_traces)

    while True:
        # Let the player be able to move one step at a time.
        try:
            direction = input("> ").lower()
        except ValueError:
            print("Invalid direction. Try again.")
        else:
            clear_screen()

            # Make help available to the player at any time.
            if direction == 'help':
                print_help()
            # Let the player leave the game at any moment.
            elif direction == 'quit':
                exit_game()
            elif direction == 'up':
                # Don't let the player go beyond the top border.
                if (player['y'] + 1) > max(y_axis):
                    print('You hit a wall. Try going in another direction.')
                else:
                    print('Went UP one step.')
                    player_traces.append(tuple([player['x'], player['y']]))
                    player['y'] += 1
            elif direction == 'down':
                # Don't let the player go beyond the bottom border.
                if (player['y'] - 1) < min(y_axis):
                    print('You hit a wall. Try going in another direction.')
                else:
                    print('Went DOWN one step.')
                    player_traces.append(tuple([player['x'], player['y']]))
                    player['y'] -= 1
            elif direction == 'left':
                # Don't let the player go beyond the left border.
                if (player['x'] - 1) < min(x_axis):
                    print('You hit a wall. Try going in another direction.')
                else:
                    print('Went LEFT one step.')
                    player_traces.append(tuple([player['x'], player['y']]))
                    player['x'] -= 1
            elif direction == 'right':
                # Don't let the player go beyond the right border.
                if (player['x'] + 1) > max(x_axis):
                    print('You hit a wall. Try going in another direction.')
                else:
                    print('Went RIGHT one step.')
                    player_traces.append(tuple([player['x'], player['y']]))
                    player['x'] += 1
            else:
                print('Wrong direction. Try again.')

        # Notify user of his/her new location.
        print_coor(player)
        print_map(x_axis, y_axis, player, player_traces)

        # Make character die if it lands on the monster.
        if player['x'] == monster['x'] and player['y'] == monster['y']:
            # Player loses the game if character dies and the game ends.
            print("As soon as you step into a new area, you are caught by "
                  "the nefarious creature who drags you to the very doors of hell.")
            # Ask user if he/she wants to play again once game is over.
            play_again()

        # Player wins if character reaches the door.
        if player['x'] == door['x'] and player['y'] == door['y']:
            print("You find the exit! Without looking back you run desperately "
                  "while feeling the ominus presence rushing after you. But "
                  "you finally make it through in one peace. The door closes "
                  "and you never look back. Congratulations!")
            # Ask user if he/she wants to play again once game is over.
            play_again()

play()