One might argue that Bozja is not supposed to be balanced, but this action still manages to be a huge outlier in the overall power scheme compared to everything else lost actions have to offer.

Overall, it's the second strongest action in the entire game in regards to raw potency (300 intital + 7000 more over 60 seconds), with only melee limit break 3 actually outdoing it (9K potency), but it has one major perk that pushes it leaps and bounds ahead, which is that it benefits from buffs/debuffs.

Limit breaks are specifically coded to not gain damage from virtually every form of buff/debuff available due to how bloated their potencies already are, but this action is not subject to the same restriction, meaning that when stacked with the abundance of buffs/debuffs lost actions and essences have to offer, it goes from being extremely strong to practically game-breaking and capable of wiping out weaker bosses in one application.

The next best thing in terms of raw potency from lost actions is Lost Slash, which has base 800 potency and does triple damage when dealing a critical, but it still comes nowhere near Lost Flare Star's maximum potential even when boosted by Lost Focus (Which is not practical outside of openers due to how long it takes to hit max stacks of the buff).

I think for the sake of preventing it from completely dwarving other lost actions in damage potential it should be given the limit break treatment and not be allowed to benefit from any damage increasing effects on either the user or the target.

It's still an extremely powerful tool without any further damage increases; being an infinite use, AoE, instant cast damage over time that hits harder then a level three ranged/caster limit break over its duration and its only real restrictions being the MP cost (Which can be easily mitigated by using a Resistance Ether Kit or just being a BLM) and not being able to apply multiple instances of the debuff to a single target (Which is irrelevant when soloing).