@Rebecca G10. mrmicrowaveoven is right. It takes a lot of time, a lot of blasters and a lot of upgrades. I also found that you can 'dig' your way above all of it and attack both sides simultaneously. this was really helpful for me to work it from the top down. I also vacuumed out my creep from everywhere else to pump it into that chamber. you also have to set up warps to get energy to your blasters efficiently, or they will run out quickly. make sure you set up reactors all over the place. dig lines everywhere and fill the trenches with reactors.
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