It’s yet another ‘feed relic threshold data into the computer’ frustration algorithm event, like p4 GAS.
There is No Reason to make waves 1-3 an insanely easy, time consuming chore before a rng heavy phase 4, besides frustration...and same goes for wave 8. It’s mostly a boring slogfest, where the only fun is 20% of the encounter.
Hope you timed thrawns TM perfectly or Teebo “might” one shot your R4 full Prot Droideka.
‘Just keep trying’ and hope it’ll get better is the mind set of an addict.