An absolutely worthy contender in the world of desktop physics games. This has not been done before to my knowledge and you did it well. 5/5, good stuff man. My suggestion is to make the graphics and theme more unique. Add some flare to it - use less colors in your color scheme, but improve upon what your engine does well. A+
Here is how I beat level 4 losing no lives on hard:
http://img530.imageshack.us/img530/6455/desertmoon04.jpg
Start with the 2 on the corners and 1 in the middle. Then add accordingly as you reach $400 every few rounds. Then, every round from 11 to 19, use one single sentinel (2) and only use your mouse to target the aliens, not the zombie men. On round 20, use a sentinel, count to 10, then use a ship-beam attack (4). You will annihilate them all.
+-+-+- Changes This Game Needs -+-+-+ Here is a short list of the major changes this game needs so far. 1) Upgraded Inventory Listing, More Room!, 2) Drop Item Ability, 3) Make Items Stackable!, 4) Make QUEST Experience Higher - We'd like 10-20% EXP per quest at higher levels, not 1-2% EXP!, 5) Make CRAFTING Better - Allow it to give us really unique components that non-crafters can not attain., 6) But most importantly - Keep adding items and zones that are relevant to the genre and that we are accustomed to! GREAT GAME AND KEEP UP THE GOOD WORK! Just a few changes will make it perfect.
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