amb1, Welcome. Many people play this game to see how long they can last in Survival Mode. They build up their defenses and energy collection to 32 (which is the maximum so don't bother building hundreds of reactors), then they turn on Survival Mode and record the max time reached. There are many ways to play this game. None of them are wrong or better, they're just different goals.
frogman215: Several people, myself included, have solved 11/7. As written earlier, please go back in the Comments to that date and read 3 detailed posts by iMiPi. Here is the start iMiPi wrote: After you collected the upgrades fly to the northwest top elevation level. There I have built structures in this order (and this also doesn't have to be the most effective order) - 1 collector, 3 reactors one by one and as soon as energy production was enough to build more than one structure: 1 mortar (you can deactivate it to avoid deficit), 1 blaster (DISARM), 1 reactor, 2 collectors. The last of these collectors was already an expansion on the top level build onto a surface previously covered by creeper, and I did NOT attack the creeper until moving the city a little bit south to shorten all later packet delivery paths.
@JaredJames: Go back to the comments dated Nov 7 by iMiPi. There are 3 in a row which explain in detail how to defeat that level in record time. Good luck.
@carusoo Thanks. I only got the 1:23 once. Several other attempts were 1:24 and up. Perhaps this is the once a month puzzle that hawk45 (and now iMiPi) and you will let me have best time. :-)
@elwaryn: iMiPi has posted several comments explaining his method for doing 11/7 in about 8 minutes. You might want to read those for some excellent suggestions.
11/6 - 4:53 Congrats Zyzyzyryxy. If you used hawk45's layout as I did, neither of us are better than the teacher. We are following in the footsteps of the pathfinder. However, any better time is a good time. Don't forget carusoo, he's probably lurking in the shadows with a time we will all envy. :-)
 "Creeper World: Evermore"){kind=icon}