All depends on which missions you do. With a neural a good many of the missions are between 2.3 and 3.0 xp/energy. For the sake of argument, let's assume an average ratio of 2.5. To go from 649 to 650, you need 25,980 xp. That gives a total energy required of 10,392 which would be pretty close to 16x Rank. So the lowest energy to rank ratio I would personally be comfortable with in order to autorank on missions would be 17x.

And, unlike NPCing, I would figure that it would be harder to maintain over a longer period of time.
For one, there are NPCs like the Gx Prison that actually give you rank points.
For two, the NPC farming is how you find the best stuff (terraformers) to up grade your planets.
Unless someone is feeding you awesome artifact planets, I think it would be much harder to constantly auto rank from missions.

Don't get me wrong. Not trying to rain on your parade. I salute you for setting a new goal.

Not just harder. It would be impossible unless you could come up with a bunch of missions that give about 3.5 exp per energy.

Few things:

1. Didn't know Frail did it on Sithons. bhahaha. I thought he was shooting the whole time.

2. I am missing where it is just 1 rescued prisoner per lvl? I don't understand the code you supplied at the end.

3. I am not doubting your math, but the practicality of implementing it seems harder than auto ranking by npc kills; mainly for the reason already stated (artifact planet production increases as you increase in rank because you have farmed more goodies).

In order for a 100 rank to start along this path, they would need ~1700 energy.
And by rank 200, they would need ~3400 to stay 17x ahead (a difference of 1700).

500 of it comes from ranking (5x100).
+ 300 of it from prisoners (3x100)

= 800 total

leaving you (1700-800)= 900 short

meh. shouldnt a done it in my head. dont know where i messed up but it should be 2.9 ish exp per energy to be sustainable. thats before any sort of bonus.

The key to doing this is artifact production. Not only do you need sufficient prisoner draws to maintain it, but you need to draw loads of calming amps and halcyons. Otherwise anyone with a handful of spy probes is going to see the great big "kick me" sign on your hull...

my number were no artis involved. other than a neural rsl and whatever it took to get to 10x rank in energy

Loving the debate about this. I never intended to try and make this sustainable... just thought it would be fun to try and hit a point where I could get a few ranks only doing missions. Killing thousands of NPCs every couple days gets tedious...

Although, after looking at Darth's formula there, I do think it would be manageable to do - if not indefinitely, then at least for a decent amount of time. My artifact production isn't amazing, but I get 4-5 rescued prisoners per day on average and that's with our base primarily focusing on research at the moment. This is looking like it should be fun...

I was gonna try doing it off Controlling the Anomaly but I think my EM supply will go poof.