This is a fairly unforgiving hold. Remember you do not need to complete any part of the accessory swap to conquer (defeat 23rd Jailer) the hold. This means you need not waste HP on rooms such as Cell Block A: Once East, instead saving it for defeating the enemies of the final section of Imperial Defense.
There are a variety of strategies that can help you get past this tricky point. One is to use the aumtlich merchants to trade HP for a higher ATK and DEF, though the HP loss is costly and will not benefit the player if they did not have enough HP in the first place. Depending on how many hit points you currently have, you should either restart the entire hold or avoid participating in the accessory chain altogether. The former will ensure a better playthrough that might let you win the game while the latter will save you time, assuming the hold has not yet been rendered unsolvable by that point.
Basically, your best bet is to restore to before entering the accessory swap.
Keep in mind that, if your intention is to defeat the harder boss (Vat Keeper), you will need a ridiculous amount of HP and greckles. This is impossible on the first playthrough; you should not attempt it until you have conquered the hold.
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It was going well until it exploded.
~Scott Manley
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