Once I figured out the pathing, it was pretty easy to find an easy-to-defend spot in every room. Of course, I needed 5 survivors and the upgraded pistol and machine gun, but those were pretty easy to get. SUGGESTION: Add room-based zombie abilities (e.g. in Medical Room they get a chemical attack, and you have to visit the health console from time to time to survive). Make concentrated piles of corpses dangerous (this will force players to move around rather than guard one easy position) by making them heal zombies, empower zombies (+speed), and/or spawn new zombies. It's not a bad game; it just got old too fast, and I think harder enemies would help a lot.
@sirblimpo, the medical data out there don't support the idea that carpal tunnel syndrome is caused by mouse clicking. Repeated clicking is more likely to make you suffer from a less-exotic-sounding repetitive strain injury, such as tendinitis.
thegmc, I was bothered by the shields thing, too. Then I realized that it's possible to beat a large fraction of the battles without taking risks during the shields stage-- either by not taking any planets, by only taking planets that are very near to your own, or by letting the computers launch first and taking whatever planet they didn't target. I still think the shields thing is less-than-ideal game design (it would be better if there were a delay on the shield appearing, so ships already enroute would get a chance to fight), but it's not as bad as I at first thought.
Strategy: Abuse planet shields and predictable computer AI. The AI won't save up ships if it sees a planet it thinks it can capture. So, if you have a planet with 1 ship and there are three AIs, ALL THREE will repeatedly attack the planet, killing each other while you sit back and save up on your other planets. Also, during shields, a computer will attack a neutral if it looks like you might soften it (but not capture it). Launch twice in a row at a nearby neutral: The first launch makes the computer attack; the second launch captures the planet (if you're fast) and makes the computer go splat on your shield.
So far, this game looks suspiciously like it's heavy on the "see how fast you can handle awkward buy/sell/move controls" aspect and light on the actual tower defense aspect.
I just beat the game with Victor IV (the fewest possible deaths, because there are three spots where you have to trap yourself to open the way forward). It's the same ending-- I see five ghosts, even though there were only three other Victors before the one who completed the game. Maybe add a different ending for us speed-run junkies? :-)
The end screen shows five ghosts, even when Victor V completes the game. Maybe have a different ending for people who go to the trouble of winning in as few lives as possible? (I know, I think it's possible for Victor IV to beat the game, but he has to be extremely quick, and I haven't pulled it off yet).
I found the traps to be reasonable, but I can see why some people thought they were cheap. My suggestion: If you make a sequel, to satisfy both groups of people, include difficulty levels. Hard = many traps. Normal = fewer traps, especially along the paths you have to run repeatedly. Thanks for the fun game!
Er, the "hard" version of endless mode crashed before it got hard. I found myself at round 22 with way more money than I could spend and enough splash damage to kill an arbitrarily large number of the monster types I was seeing. The game's balance could use some tweaking.
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Good comment :)