My Dungeon Game! Feedback greatly appreciated

import random
import os


CELLS_NORMAL = [
    (0, 0), (1, 0), (2, 0), (3, 0), (4, 0),
    (0, 1), (1, 1), (2, 1), (3, 1), (4, 1),
    (0, 2), (1, 2), (2, 2), (3, 2), (4, 2),
    (0, 3), (1, 3), (2, 3), (3, 3), (4, 3),
    (0, 4), (1, 4), (2, 4), (3, 4), (4, 4)
]

CELLS_HARD = [
    (0, 0), (1, 0), (2, 0), (3, 0), (4, 0), (5, 0), (6, 0), (7, 0), (8, 0), (9, 0),
    (0, 1), (1, 1), (2, 1), (3, 1), (4, 1), (5, 1), (6, 1), (7, 1), (8, 1), (9, 1),
    (0, 2), (1, 2), (2, 2), (3, 2), (4, 2), (5, 2), (6, 2), (7, 2), (8, 2), (9, 2),
    (0, 3), (1, 3), (2, 3), (3, 3), (4, 3), (5, 3), (6, 3), (7, 3), (8, 3), (9, 3),
    (0, 4), (1, 4), (2, 4), (3, 4), (4, 4), (5, 4), (6, 4), (7, 4), (8, 4), (9, 4),
    (0, 5), (1, 5), (2, 5), (3, 5), (4, 5), (5, 5), (6, 5), (7, 5), (8, 5), (9, 5),
    (0, 6), (1, 6), (2, 6), (3, 6), (4, 6), (5, 6), (6, 6), (7, 6), (8, 6), (9, 6),
    (0, 7), (1, 7), (2, 7), (3, 7), (4, 7), (5, 7), (6, 7), (7, 7), (8, 7), (9, 7),
    (0, 8), (1, 8), (2, 8), (3, 8), (4, 8), (5, 8), (6, 8), (7, 8), (8, 8), (9, 8),
    (0, 9), (1, 9), (2, 9), (3, 9), (4, 9), (5, 9), (6, 9), (7, 9), (8, 9), (9, 9),
]


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


def move_player(player, move):
    x, y = player
    if move == "UP":
        y -= 1
    if move == "DOWN":
        y += 1
    if move == "LEFT":
        x -= 1
    if move == "RIGHT":
        x += 1
    return x, y


def monster_encounter(hp):
    hp -= 1
    input("You ran into a monster! You managed to fight him off, but your HP is now {}.".format(hp))
    return hp


def game_loop_normal():
    player, monster, door = get_locations_normal()
    hp = 3
    while True:
        clear_screen()
        draw_map_normal(player)
        valid_moves = valid_moves_normal(player)
        print("You are playing Dungeon of Death on NORMAL mode\n"
              "Your current location is {}".format(player))
        print("You have {} HP".format(hp))
        print("Which direction would you like to move? You can go {}".format(", ".join(valid_moves)))
        print("<Type 'Q' to quit.>")
        move = input(">    ").upper()

        if move == "Q":
            clear_screen()
            print("Thanks for playing!")
            break
        if move in valid_moves:
            player = move_player(player, move)
            if player == monster:
                if hp > 1:
                    hp = monster_encounter(hp)
                    monster = random.choice(CELLS_NORMAL)
                    while monster == player or monster == door:
                        monster = random.choice(CELLS_NORMAL)
                else:
                    play_again_normal()
                    break
            if player == door:
                print("\n** CONGRATULATIONS! You found the escape door!")
                print("You've escaped death.....this time!")
                play_again = input("Would you like to try again? [Y/N]\n"
                                   ">   ").lower()
                if play_again == "y" or play_again == "yes":
                    game_loop_normal()
                else:
                    clear_screen()
                    input("Thanks for playing! I hope you had fun!")
                    break

        else:
            input("Sorry, that's not a valid direction! Press <ENTER> to try again.")
            continue


def get_locations_normal():
    return random.sample(CELLS_NORMAL, 3)


def valid_moves_normal(player):
    x, y = player
    moves = ["UP", "DOWN", "LEFT", "RIGHT"]
    if x == 0:
        moves.remove("LEFT")
    if x == 4:
        moves.remove("RIGHT")
    if y == 0:
        moves.remove("UP")
    if y == 4:
        moves.remove("DOWN")
    return moves


def draw_map_normal(player):
    print(" _" * 5)
    for cell in CELLS_NORMAL:
        x, y = cell
        if player == cell:
            if x == 0:
                print("|X|", end="")
            elif x == 4:
                print("X|")
            else:
                print("X|", end="")     
        elif x == 0:
            print("|_|", end="")
        elif x == 4:
            print("_|")
        else:
            print("_|", end="")


def play_again_normal():
    print("\n** YOU RAN INTO THE MONSTER! Your health was too low to get away this time....You lose **")
    print("\nBetter luck next time!")
    play_again = input("Would you like to try again? [Y/N]\n"
                       ">   ").lower()
    if play_again == "y" or play_again == "yes":
        game_loop_normal()
    else:
        clear_screen()
        print("Thanks for playing! I hope you had fun!")


def game_loop_hard():
    player, monster1, monster2, monster3, door = get_locations_hard()
    hp = 3
    while True:
        clear_screen()
        draw_map_hard(player)
        valid_moves = valid_moves_hard(player)
        print("You are playing Dungeon of Death on HARD mode\n"
              "Your current location is {}".format(player))
        print("You have {} HP".format(hp))
        print("Which direction would you like to move? You can go {}".format(", ".join(valid_moves)))
        print("<Type 'Q' to quit.>")
        move = input(">    ").upper()

        if move == "Q":
            clear_screen()
            print("Thanks for playing!")
            break
        if move in valid_moves:
            player = move_player(player, move)
            if player == monster1:
                if hp > 1:
                    hp = monster_encounter(hp)
                    monster1 = random.choice(CELLS_HARD)
                    while monster1 == player or monster1 == door or monster1 == monster2 or monster1 == monster3:
                        monster1 = random.choice(CELLS_HARD)
                else:
                    play_again_hard()
                    break
            if player == monster2:
                if hp > 1:
                    hp = monster_encounter(hp)
                    monster2 = random.choice(CELLS_HARD)
                    while monster2 == player or monster2 == door or monster2 == monster1 or monster2 == monster3:
                        monster2 = random.choice(CELLS_HARD)
                else:
                    play_again_hard()
                    break
            if player == monster3:
                if hp > 1:
                    hp = monster_encounter(hp)
                    monster3 = random.choice(CELLS_HARD)
                    while monster3 == player or monster3 == door or monster3 == monster2 or monster3 == monster1:
                        monster3 = random.choice(CELLS_HARD)
                else:
                    play_again_hard()
                    break
            if player == door:
                print("\n** CONGRATULATIONS! You found the escape door!")
                print("You've escaped death.....this time!")
                play_again = input("Would you like to try again? [Y/N]\n"
                                   ">   ").lower()
                if play_again == "y" or play_again == "yes":
                    game_loop_normal()
                else:
                    clear_screen()
                    input("Thanks for playing! I hope you had fun!")
                    break

        else:
            input("Sorry, that's not a valid direction! Press <ENTER> to try again.")
            continue


def get_locations_hard():
    return random.sample(CELLS_HARD, 5)


def valid_moves_hard(player):
    x, y = player
    moves = ["UP", "DOWN", "LEFT", "RIGHT"]
    if x == 0:
        moves.remove("LEFT")
    if x == 9:
        moves.remove("RIGHT")
    if y == 0:
        moves.remove("UP")
    if y == 9:
        moves.remove("DOWN")
    return moves


def draw_map_hard(player):
    print(" _" * 10)
    for cell in CELLS_HARD:
        x, y = cell
        if player == cell:
            if x == 0:
                print("|X|", end="")
            elif x == 9:
                print("X|")
            else:
                print("X|", end="")           
        elif x == 0:
            print("|_|", end="")
        elif x == 9:
            print("_|")
        else:
            print("_|", end="")


def play_again_hard():
    print("\n** YOU RAN INTO THE MONSTER! Your health was too low to get away this time....You lose **")
    print("\nBetter luck next time!")
    play_again = input("Would you like to try again? [Y/N]\n"
                       ">   ").lower()
    if play_again == "y" or play_again == "yes":
        game_loop_hard()
    else:
        clear_screen()
        print("Thanks for playing! I hope you had fun!")


#Explain game in welcome screen
#Make Normal/Hard modes, normal uses less cells and has 1 monster, hard uses more cells, has more monsters
#Make HP system, player starts with X hp, and loses Y hp each monster encounter, dies at 0 HP
#Make scoreboard system to keep track of wins/losses for multiple plays
#possibly make some kind of randomized battle system for monster encounters?
clear_screen()
input("Welcome to the DUNGEON OF DEATH! Press <ENTER> to begin!")
clear_screen()
difficulty = input("Please choose [Normal/Hard]: \n"
                   "Normal - Smaller dungeon size, one monster\n"
                   "Hard - Large Dungeon, more monsters\n\n"
                   ">    ").lower()
while difficulty != "normal" and difficulty != "hard":
    difficulty = input("I didn't recognize that, please enter the difficulty you would like to play on! [Normal/Hard]\n"
                       ">    ").lower()
if difficulty == "normal":
    game_loop_normal()
else:
    game_loop_hard()