Protector of Encaria achievement

[stryker412]

How low do you have to keep the poison levels to get the achievement?

[stryker412]

I found the answer, you must keep it below 1000.

[captainjy]

So what is the secret with this one? I managed 1200 level. Do you need to destroy all the transport vessels or all the harvesting stations or both?

[stryker412]

Kill the stations right away.

[ScottEvil30]

I did this by splitting my ships into two groups of two (one cruiser/one battleship in each group) and working through the planets that way. Its so hard to do it with a single group.