Was playing on hard, (making my way up to harder and nightmare), and had nobody on guard duty vs. 330 zombies + horde. My defense was 50 and I had a 90% chance of losing. I won.
Stop thumbing down people who are saying the save is broken. IT IS BROKEN. Jeez. If you want to finish this game, play it all in one sitting or be prepared to start from scratch.
I enjoy challenging, but could you make it so I don't have to restart the game just to pick heroes to beat the big red guy and his girl. That combo is just retarded. I could beat it given more phoenix downs too, but you limit it to 3. My only complaint.
To beat level 10: Take the closest empty cell and stay attached to it. When you have about 18 on it, immediately attack the left most enemy cell. Cut the connection when the enemy reaches 13 or 14 hp so the tentacle you cut takes it over. Hook this one up to the giant cell, cutting when needed to keep the reds from taking it. Hook the cell you used to attack up to the giant cell and then just wait it out.