This one stood out for me somehow. I like the mechanics, the basic principle behind it certainly has potential. As previously mentioned, the ice seems to melt too fast (or my steering skills are too poor?). After about 10$ of collected ice worth, there are more red-blooded eyed pinguins than my cannon can handle (seems like 40+?). Once arriving at the trusted port, nothing but water in my crates. I believe this happened in real life too, so it might be called realistic?
Room for improvement: Decrease the rate of decay of the ice to about 25% of its current value, make bigger guns available in the shop, increase the shooting rate, increase the toughness of the men.