Friday, January 23, 2009

Tower Defense Redux

Looks like there was at least a little bit of interest in my last post about Tower Defense games on the iPod, so here's a followup.

First, I'll go over the bonus challenge mode "This is Sparta" in the game Tap Defense. I finally got around to beating this mode in Easy and Medium, and both of them rely pretty heavily on the Earthquake tower. To recap, the This is Sparta mode has these special rules:

Start with 3 lives, rather than 20
Start with 3 halos, rather than 0
Start with 300 gold (in honor of the movie "300")
9 Towers Max, as opposed to normal rules where you're only limited by space and gold
3 of each tower max

This is Sparta: Easy mode
First, I used two of the three starting halos to increase my interest rate. You want to be in the position, in the second half of your game (round 21+) to be really racking up the money to a couple thousand. More on that later. To start, get two arrow towers along the bottom half of the map, as shown in the picture. They don't have to be exactly in those places, but preferably they should be able to reach both the bottom area of the path and the part of the path that runs through the middle. Like in the normal game, you'll want to use as few towers as possible at as low levels as possible while still killing all enemies, because that saves you money.

Anyway, this placement for your first two arrow towers should be fine, though sometimes the game throws a bit of a curveball at you and bunches up those gremlins such that the arrows can't get 'em all at once. In that case, place an arrow tower near the upper right corner of the screen. Unfortunately, it can be a bit tricky knowing whether your towers will cover adequately until it's too late, especially if you're trying to minimize your money spent. I had to restart quite a few times and use trial and error until I got a better feel for how little coverage I could get away with. The first few rounds, arrows should suffice. Since you've already used your max of 3 arrow towers, it's a good idea to upgrade them. It's truly amazing what difference a level 3 Arrow tower makes. In fact, a single level 3 arrow tower can likely handle the first three rounds of enemies no problem. But of course that would be more costly. Wait 'til you get more money, and you'll want to upgrade all three arrow towers to level two some time before round 10.

For the first round of succubi and then demons, you may want a cannon in there somewhere. Preferably it should be in the top half of the map, so the arrows can soften up the enemies first and the cannon can make the kill. Despite the game's advice, fire cats, at least in the early rounds, need not be dealt with using water towers. Your upgraded arrows and single cannon tower should suffice. I actually used my first 6 halos for interest rate. Upgrade all your arrow towers to level three when you get into the teen rounds, and you may want a second cannon and a water tower as well. That brings you to 6/9 towers. Also keep in mind that arrow towers can go up to level 4. In the first 2/3 of the game, it's not a good idea to make all three of your arrow towers level 4, though one level 4 arrow tower can be really really helpful, and often kill enemies in one hit. The downside is that its refire rate is very, very slow.

When you get above round 20, if you've been using your money wisely (more on that later), you should have enough to get an earthquake tower (of course, you will want to save two halos to research it). I'm not entirely sure on the total amount of money, but have at least 2000 gold to spend on it. At level 3, the earthquake tower has enormous range, and does 2000 damage. Since you're severely limited in the number of towers you can create, the range and damage done by the earthquake is invaluable. With the earthquake and other towers in the positions shown in my picture, you should do fine. Just be sure to use your earthquakes liberally, because at level three the recharge time is very good. Later in the game, it might be helpful to replace an arrow tower with a level 3 storm tower to quickly whittle some enemy energy down before being pulverized by the earthquake.

Congrats! You've beaten This is Sparta on Easy!

Here are some more tips for money.
-Never ever create a tower right at the end of a round. You're spending money on it but not getting any utility for that round, and even worse, you won't get as much interest. Wait 'til the beginning of the next round to build towers. If you must place a tower as an emergency measure, do it as soon as you can so you can get the most utility out of it for that round.
-If your interest rate is high enough, and depending on the tower, you can try selling a tower right before the round ends, so you get extra interest from it. This is generally not a good idea for, say, a level 3 Storm tower or Earthquake tower, because you'll probably lose more than you gain.
-This applies more to the normal game than This is Sparta, but still applies: often the benefit you get from upgrading your towers (more damage, higher refire rate) outweighs the benefit from simply adding more level 1 towers, despite the fact that adding more towers may be cheaper. You want to maximize your interest rate, but doing so at the cost of letting a few enemies through is not a good compromise, in my opinion. And when you're playing the Sudden Death mode or This is Sparta, it's a terrible, unthinkable compromise.

I'm running long, so I'll do the Medium tips very quickly.

This is Sparta: Medium mode
The tips from Easy mode will also work here. The difference is that since the path is so much shorter and less circuitous, you have much less leeway to kill the enemies. You have to get them fast, or else. So you'll be upgrading your arrow towers sooner and adding cannons sooner, in order to kill the baddies at an earlier point on the path. It's important to use the top and bottom of the screen in later rounds, because upgraded towers in the middle of the screen will generally just follow the one enemy that's at the front of the pack. There's really only one place you should put your level three earthquake tower for maximum coverage. See picture.

That's it! I was going to talk about two other Tower Defense games, Zombie Attack and The Creeps! But perhaps next time.