If you want to get to a specific depth without taking damage, just jump your ship out of the game area. At the beginning head up and to the left - you'll end up in the blackness inside the walls. Here you can zip down to your desired depth, then scoot right back into the game area at will.
I need to agree with Kaetzer here. This has all the elements of a truly fantastic game. If you remade this with a more powerful engine to handle the lag, and perhaps even made it standalone, I can see it being hugely successful. Here's hoping you do!
Even knowing the nuke's coming, dropping civilians off at the church makes sense. It is somewhat more reinforced than other buildings, most likely has a basement, is already stocked with supplies, and is single-story and therefore slightly more likely to survive the blast.
Minigun: LMG with 2x Relativity Trigger, 2x Quantum Xerox.
This thing destroys more or less anything you point it at in seconds... As well as everything even slightly near it.
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