I used to be able to get 53598 after beating level 35, but they changed something years ago. It requires a lot more lightning tower spam now, but I can still manage 42768 with overly aggressive tower spam. It's likely possible to get closer to 45k, but I'm not willing to take the time to optimize the last few levels. 3x level 3 stone towers gets you to 10, swap to 1x level 3 lightning tower, add a level 2 lightning tower for 12, upgrade it to level 3 for level 18, add a third level 3 lightning tower for 24, a 4th for 30, 2 more for 31. From there, it's just about finding the right number of additional lightning towers to pass the next level. Placement is everything in this game.
I have no idea if anyone will ever see this that will care at this point, but I decided to make a Reactor Idle discord server so the community can still exist and have chat rooms again. https://discord.gg/zQkHdSnTyQ
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