I think I like this mod, thanks for making it!

I haven’t played it yet, only looked around in Factoriopedia. I can imagine how to build everything but one aspect seems to be disproportionately difficult: producing biter eggs (for productivity 3 modules and biolabs) before going to Aquilo and unlocking crafting of captive biter spawners. In normal Space Age you find a wild spawner, capture it, then feed it 1 bioflux/min to get up to 30 eggs/min. To compensate the absence of wild spawners this mod adds the Egg Mutation recipe. I find the idea of this recipe funny but not only is it very expensive (20 bioflux for a single egg, 600 times more than with a captive spawner) it’s also quite dangerous because it can only be used on Nauvis but requires pentapod eggs that can only be obtained on Gleba and hatch after 15 minutes.

Am I missing something? As the mod stands it looks impractical to craft prod3 modules by the hundreds before going to Aquilo, like I normally would in vanilla Space Age.

I think Egg Mutation being expensive and dangerous would be fine (or even fun) if it can be used only once (like babysitting a dozen pentapod eggs in a single trip) to bootstrap some other process. Should this mod change the Captive biter spawner tech to not require cryogenic science (nor cold fluoroketone)? Or maybe add a recipe breeding biter eggs into more eggs that is somehow not as good as captive spawner, but available with only agricultural science? Or rebalance Egg Mutation?

I even tried in editor mode to let some biter eggs hatch to see if they would form an expansion party a create a wild spawner, but without any pollution-emitting factory to attack they only walked around and eventually despawned entirely.

In regular Factorio, the challenge of pre-Aquilo biter eggs is that you need to capture a spawner somewhere inconvenient. Either you've dealt with the pain of keeping a spawner alive near you all game until you get to that point, or you're going far away to capture one. Since that kind of challenge doesn't exist in seablock, egg mutation is intentionally a bit of a pain to get you the handful of eggs you'll want for things like prod 3s and biolabs before Aquilo, and then to give you the eggs you need to to eventually start a captive spawner once you have the tech. Personally I got my labs all upgraded to biolabs pre-Aquilo by, as you said, somewhat "babysitting" the process. And if you really don't like the idea of shipping live pentapod eggs, you can always accept the (significant) efficiency loss by shipping biolabs then recycling them when you need the eggs.

With that said, I personally don't really bother much with productivity 3s until post-Aquilo, so I appreciate the feedback that if you are someone who makes them in large numbers at that point in the game, egg mutation probably feels a little too painful. The idea is, as you correctly deduced, primarily to give you a challenge to bootstrap your eggs on Nauvis.

I don't really like the idea of moving captive spawners earlier in the tree, but I can get behind the idea of some kind of recipe where you can turn biter eggs into more biter eggs at the Argicultural science level. I just think it would be important for such a recipe to be "bad" enough that you'd never seriously consider it once you get captive spawners, as that's supposed to be the real way of doing it. Generally the "bootstrap" recipes in the mod are all intentionally very bad so that they'd never be realistic to use long-term (personally, in my first Space Age playthrough I kept using Simple Coal Liquefaction on Vulcanus long after unlocking the better one because it was doing well enough and not worth the effort to change my setup). The main difference here is you get the bootstrap recipe long before the real one.

Maybe something like 10 Biter Eggs + 2 U235 + 10 Bioflux = 11 Biter Eggs, in a Biochamber, with a 60s crafting time (really 30s because crafting speed of 2). Maybe the biter eggs are also 50% spoiled (regardless of input), so much like pentapod eggs you can keep your eggs fresh as long as you keep cycling the recipe, but the output is automatically less valuable than a captive spawner?

shipping biolabs then recycling them when you need the eggs

Biolabs recycle to themselves, but even if they didn’t that doesn’t solve the problem of how to get eggs in the first place?

Gleba is usually the last inner planet I go to, so Aquilo is not too far behind and maybe it’s not too terrible if fully automated eggs is delayed. But it’s a serious hit to the reward v.s. effort ratio of going to Gleba, "removing" two of the three unlocks (with stack inserters) I care most about.

I think that recipe idea would work, I can see myself leaving it running unattended more than shipping live pentapod eggs.

Speaking of bootstrap recipes being intentionally bad (maybe this should be another thread), is there a better way to get coal on Nauvis than growing trees for charcoal? 45 easily usable plots per agri tower works out to only 1.5 coal/s on average, equivalent to only 3 miners. Sounds like lots of farming is needed to get mediocre steam power and smelter fuel?

Oops, I meant to say shipping and recycling Biochambers, not Biolabs.

For coal, yes you're growing trees and putting them in furnaces. You'll need to grow quite a few trees as you scale up, and getting nuclear power going should definitely be a priority. Probably worth supplementing steam with some solar before you get Nuclear going (get producing that landfill).

I actually had the coal output from wood quite a bit lower than 10x for much of my playtesting, and it was certainly doable, but a little too painful so I gradually increased it and eventually landed on 10.

Oh interesting, recycling biochambers. I think that addresses my worry with shipping live eggs and removes the need for an egg breeding recipe. Recycling loss is a good motivation to move to captive spawners as soon as available.

Sounds like Nauvis needs to dedicate a lot of space to tree farming but I guess that’s a fair trade-off for not needing miners!

Alright, if you're less convinced by the need for an egg breeding recipe, I think I'll hold off on adding one unless you or someone else say otherwise. My main concern with such a recipe is quality shenanigans - being able to mass-produce legendary biter eggs after you get your first few would be incredibly powerful, even if you do need a constant stream of other legendary resources like Bioflux and U-235. I was investigating ways to prevent the recipe from being set at higher quality and the only options I could find were a little bit hacky relying on tick handlers and the like. Doable, but not ideal. Technically you could use egg mutation to get quality biter eggs if you can get quality inputs, but I'm thinking the recipe is enough of a pain that it's not a big deal.