Extended Water Breathing Is Possible.

[Sir Tawmis]

Just tried it out.

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Just quaff Energy potions. It won't restore to full Energy, but it allows at least one person to keep breathing under water for a little longer!

[Saice]

clever

[Chimera005ao]

I thought about it, but never tried it.
Didn't end up needing to really.
But I did find some other nice thing that can help with dealing with monsters under water.

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Got trapped, and in a panic, had my alchemist craft lightning bombs. Threw them myself from the inventory. ; P

[sergregor]

That

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lightning bomb trick

is hilarious. I'd have never thought of that. If anything it should kill your party too

Regarding the use of energy potions for extended breath though? I don't really see a need for it when it's not that hard to survive long enough for the

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hold your breath puzzle

and for everything else so far, you simply need to know where the ladders are and not stay under for so long. It's not like there's any great shortage of etherweeds though so if you have an alch then I guess chug those potions.