13: Midnight Ridge

Campaign

Waves: 5

Starting Energy: 2100

Lives: 20

This is a large map with all tower slots free. As usual, you have to three entry points but the western side has two entry points which will make the enemies converge on the two roads. The bottleneck position is also located near the southwest checkpoint is placing the bulk of your troops there is recommended. Using your initial funds, set up your blockade first then place a laser tower or rocket tower in the top-middle slot and upgrade it to max. If you were able to purchase their specialization, consider changing them as well. The laser tower's quad-beam is very helpful in dealing potent laser damage to at least four enemies at once.

You'll be introduced to Wasps, fragile flying units that will boost out danger and Hulks, slow but heavily armored units that will occassionally hunker down and increase its defenses for a short period of time. LV3 MG towers and LV3 lasers can take care of them, provided that they don't rush along with other sturdier units. With a heavily defended setup, these are most likely the units that will escape and ruin your chance in getting a three-star rank in the campaign. This is in addition to the pesky medics, mites, and arctic crusaders you have to deal with before. In the last wave, icers AND wasps will join together, making it even more harder to shoot them down. Make sure that you have saved your tesla shots in the fifth wave so you can easily take out the wasps.

Veteran

Waves: 6

Starting Energy: 1850

Lives: 1

In this battle, you're only allowed to use MG and Rocket towers. You'll have to deal with mites, wasps, and icers so you have to place rocket towers near intersections where most of the enemies will most likely group together. You have to save your tesla tower shots in the last wave since annoying wasps will basically slip past your defenses. MG towers are more effective in dealing with them since they're quite hard to track individually. As much as possible, bomb the creeps as they start appearing to the north. That way, you can kill most of them instantly before they go on separate ways.

Spec Ops

Waves: 1

Starting Energy: 1400

Lives: 1

You can follow the same setup as the campaign but you have to make a few adjustments. First, wasps will appear early in the wave via the eastern road. That said, set up your primary defenses on the eastern road. After dealing with the wasps, a whole load of artic crusaders, icers, and mites will join the fray. Also, more wasps will appear on the shorter, eastern road which you can easily miss. This battle is quite hard, even if you have good upgrades purchased. The problem is that you can't get energy that fast to keep up with the enemy forces you have to deal with. One solution is to go all out with your airstrikes, reinforcements and tesla charges though you may have to take into consideration that your consumable abilities will be wasted if one enemy manages to pass through.