We really need to talk about Living Dead

[Miminming]

You may be surprised as the amount of solo play situations you can salvage pertaining to use of Holmang and Superbollide.

First off, you can utilize a healer chocobo to manage Holmang(Any type of chocobo should be sufficient to keep yourself topped off with Nascent Flash in most situations) and Superbollide, making them viable options for virtually all overworld content.
Naturally, that isn't the case Living Dead, with the cumulative 100% HP requirement being unattainable.

Secondly, sustaining potions in palace of the dead are surprisingly enough to manage both Holmang and Superbollide.
I'm not too familiar with using them, but there is a similar item in Eureka that may be sufficient for solo usage of Holmang and Superbollide in Eureka Anemos and Pagos.
Once access to Logograms is granted in Pyros and Hydatos, I can definitely vouch for logos action like Bloodbath being sufficient enough to use in tandem with Holmang and Superbollide.
Once again, that is not the case for Living Dead - which is honestly kind of sad.

Apart from straight forward running of undersized content, there are honestly quite a few contextual actions and skills accessible that may provide players with access to unique heals in solo content.
They can be often be adequate to utilize in conjunction with Holmang and Superbollide, but will virtually never be enough to get any use out of Living Dead in solo play.

Have you been in that situassion or it's just your hypotethical? First thing first if you bring healer chocobo as a tank there's almost virtually no contents that need invul in overworld that can be solo'd.
(Lvl 80 mob hunt or anything that doesn't mean to be solo'd exclude obviously because even with invul it's impossible to kill lvl 80 A class mob hunt atm)

In eureka or PotD or HoH if you still have the time to use potion or Logos, there 's NO reason to use invul, and if you are gonna argue the potion cooldown is on 5s or something, the i must say that 0.000001% of situassion is not worth counting, it's like saying you could have live if the enemy attack is missing or your attack is crit or is there's pomander of raise beside you or there's one less enemy in that floor or there's some random healer to heal you etc. etc.

[Lyth]

...

Even my chocobo is better designed for tanking than Living Dead.