LOL I thought this game was terribly hard, didn't even realize there were shields to be bought.
I almost beat the final boss at level 4 with no shield at all xD
Is there any place to buy unlimited haste potions? I think I've bought all of the ones in aeropolis, and they seem pretty vital for winning sometimes :(
For tank work I used two typhoons near the beginning, then sold them and built as many doom towers as possible in the left side middle area, then sold those all when the tank was past and built the two typhoon towers again. After the second run by the typhoons I built as many doom towers as possible near the end of the level and got all tanks down with lots of room to spare.
FINALLY downed silver maze level 25 (with lots of room to spare ;))
6 Unicorn towers and a lazer tower in each corner. Alternate one tower between fire/ice to keep the tank slowed!
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