Tried to start but,

[DaytradeCentral]

run.py

pygame 1.9.5
Hello from the pygame community. https://www.pygame.org/contribute.html
Traceback (most recent call last):
File "run.py", line 6, in
from main_menu.main_menu import MainMenu
File "/home/tintin/Tower-Defense-Game/main_menu/main_menu.py", line 1, in
from game import Game
File "/home/tintin/Tower-Defense-Game/game.py", line 3, in
from enemies.scorpion import Scorpion
File "/home/tintin/Tower-Defense-Game/enemies/scorpion.py", line 11, in
pygame.image.load(os.path.join("game_assets/enemies/1", "1_enemies_1_run_0" + add_str + ".png")),
pygame.error: Couldn't open game_assets/enemies/1/1_enemies_1_run_000.png

game.py

pygame 1.9.5
Hello from the pygame community. https://www.pygame.org/contribute.html
Traceback (most recent call last):
File "game.py", line 3, in
from enemies.scorpion import Scorpion
File "/home/tintin/Tower-Defense-Game/enemies/scorpion.py", line 11, in
pygame.image.load(os.path.join("game_assets/enemies/1", "1_enemies_1_run_0" + add_str + ".png")),
pygame.error: Couldn't open game_assets/enemies/1/1_enemies_1_run_000.png

[jsc57x]

This is not an issue. You should read the readme. You don't have the requested game assets (like it is also shown in the tracebacks). Therefore you are unable to launch the game.
But you can create your own assets and use them :)

[AlkisPis]

This is not an issue. You should read the readme. You don't have the requested game assets (like it is also shown in the tracebacks). Therefore you are unable to launch the game. But you can create your own assets and use them :)

This makes no sense. How can one create 30 own assets to replace the original ones? Even if one could do that and the game could still be run, the result would certainly be monstrous.

[jsc57x]

Thanks for digging me up. Nobody said it would make sense to create the assets yourself or it does look good then. But this is a possible solution (in fact the updated readme suggest its the ONLY solution...)