I've been working on this for the past several months. It's not 100% done, but it's about where I want it.
Six pesky little penguin chicks have run off and gotten themselves lost in the mysterious ruins. You are the only one brave enough to rescue them! Smash away the iceblocks with your snowballs. To roll a snowball, hold the fire button and walk around the screen. Release the button to throw it. But be careful, this ice is so cold, you will be frozen solid if you touch it! To make matters worse, all this activity has activated the old sentries. They will track your position and start rebuilding the fortress. Take them out with a snowball. If you save six chics without getting frozen you earn an extra penguin.
Right difficulty toggles flashing effects and B/W toggles NTSC and PAL60.
I still need to adjust the startimg positions for each level and some of the colors in later levels don't make a lot of sense. The code is an uncommented mess, so proceed with caution.
Thanks for playing!