#200 had basically two proposals: allowing princess larvae to be created, and changing the effects of the hatchery block. I'm splitting the second proposal out into its own GitHub issue.

This proposal is to change the effect of the hatchery block. Instead of producing larvae at random inside the hatchery block, it would change what gets placed in the alveary's output slots when the queen dies. What I'm suggesting is that the hatchery block has the following effect:

• Without hatchery block in the alveary:
  • 1 princess, 1-4 drones end up in the output slots when the queen dies (like normal)
• With hatchery block:
  • 1 royal larva, and 1-4 "normal" larvae end up in the output slots when the queen dies

(The "royal larva" is from suggestion #200, and would turn into a princess when put in an incubator).

Note: if the queen is of Ignoble stock, there's a chance of getting no royal larva in the output -- the exact same chance as there would have been of getting no princess.

The revised version of the hatchery block would not have a GUI. Instead, it would be like the Alveary Rain Shield: if it's in the alveary structure, it changes how the alveary behaves (drop larvae + royal larva instead of drones+princess). And if it's not in the alveary structure, then the normal behavior happens.

Note that if the "royal larva" idea from #200 is not added to the game, then the hatchery block would cause there to be 1 princess and 1-4 larvae in the alveary's output. So this proposal could still be implemented independently of #200.

Note that the current status of #200 has a "Royal Jelly Frame" item being necessary in order to get a Princess Larva. That's a neat idea, which could also be incorporated into this one. In that case, the hatchery block would have a GUI with a single slot for a frame, and it would ONLY accept the Royal Jelly Frame (and would not accept any other frames). Then the alveary output when the queen dies would be:

• No hatchery block in the alveary:
  • 1 princess and 1-4 drones in alveary's output slots
• Hatchery block in the alveary, which does NOT contain a Royal Jelly Frame:
  • 1 princess and 1-4 larvae in alveary's output slots
• Hatchery block in the alveary, which DOES contain a Royal Jelly Frame:
  • 1 royal larva and 1-4 larvae in alveary's output slots

As I mentioned in ForestryMC/ForestryMC#1743 (comment), I'd like to see #200 happen in 1.7.10 since that's the version I'm currently running, and if I moved to 1.10 or higher I'd lose Thaumcraft -- and I'm not ready to quit playing Thaumcraft yet. Once I get tired of Thaumcraft (which might take a year or two) I may move to a more modern Minecraft version (which will probably be 1.12 at that point), but at the moment since I want Thaumcraft, I'm stuck with either 1.7.10 or 1.8/1.9 (and Forestry doesn't support 1.8/1.9 any more, as far as I know).

Therefore, I made my suggestions for 1.7.10, since that's the version I really want to be able to keep playing for another couple of years. I'm quite willing to contribute work to make it happen, as long as the mod maintainers are okay with the idea.

Unfortunately, all we can do now is change the work of the hatchery.
Can I remove the larvae of drones, make the larvae of the princess? And make appropriate changes to genetic machines.

Sorry, we should not make any new features for 1.7.10. We can discuss it for the latest version though.

@rmunn @KorDum I am think this is a good idea. But not for 1.7.10. Forestry 1.7.10 is a final version and we only fixing major bugs of it and not adding any new features.