with the right strategy level 4 is easy. just defend until the enemy gets low on money and then advance.
but i had to restart about 20 times to figure it out.
the rest is too simple. i have beaten every other level on the first try on hard. raptors are the key to success nearly every time
why is it rated so high? its boring.
just fire randomly as aiming is senseless and call airstrike, when trucks are coming. time to get to wave 28 wasted. nothing new happens
start with upgrading the money gaining factory. you won't need to buy weapons for the first levels. that way you will have plenty of money in the later levels.
i started level 10 on hard with about 150 rocket, 20 EMP and 5 nukes. eveything else fully upgraded and full health. that way the badge is easy.
but the jackal badge does not work...