The planet with their giant super important simulation was being eaten by it (and might still be eating it, we only decoupled it from the sun)
I'm kind of surprised they haven't telaported onto it and tried shutting it down or converting it into something to nullify the sun like in the future that they attempted to make, and you gotta admit it'd make an interesting strike :p
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Almighty can destroy the sun,and it will kill any Hive,Fallen,Vex in solar system,but not even one of them want to stop the Almighty except a guardian...so i think bungie never thought about it.Because they only thought how to make this mission epic....