YO! Tip for you guys feeling nervous about your structures. If you fear one of your structures is about to die, save the game manually. Then load from that game if it dies. Safe and sound.
The waves get harder, but I found a good strategy. Found out your preferred primary weapon (low cooldown, use it a lot i.e. Pellet Gun). Load two of these. Load 2 super weapons e.g. nukes. Load one shield, preferably power shield. Switch between primary weps while one is loading, wipe out the battlefield w/ your nukes when they load, and shield yourself when enemy nuke is imminent. Ex loadout: 2 super thumpers, 2 Mr. Nukes, 1 Power Shield.
Little strategy tip: If you can terraform down to water in the middle of someone else's land, you can place a whirlpool there and watch the destruction.
Wind totem seems like the best choice for attacking. Most spells are cheap, and therefore you can spam them during attack. Lightning storm is a quick and fast attack able to take out several buildings. Whirlpool is good for harassment and, when spammed, for destroying large areas of (enemy) land. Twister can take out an enemy line, and the wind hero is cheap and gives a hero in place of the leader. Also, water storm can wipe out entire tribes. Little info I picked up.
Quick and easy way to add flat land to an ocean: Terraform a hill upwards, max 3 clicks. Add each click to the peak of the first hill. After finishing the hill, terraform down, at the center each time, until you reach the bottom. Finally, fill in the last pit, and you have a nice sized flat island.
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