I played around with the final boss health drops and there's at least some fixed logic. When you start the fight, the drone on the right will always drop health. You can play around that to create a backup health pool really quickly. After the start it gets really chaotic but I found one pretty good sweet spot. If you enter the second phase having killed 5 drones, 2 out of the next 3 drones will drop health. If you manage to distribute these 3 drops evenly, the fight is pretty much won. I'll continue to figure this out. It's somehow connected to both killing all drones and also advancing in the fight. Killing only one specific drone yields inconsistent results.
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