I like this...it gives us a good bite and makes the book sound intriguing, at least to me. I think the detail about the rash is what caught my attention first and made me keep reading. I totally understand about some aspects being too much for the pitch =)! But I think this works for me: it caught my attention, kept me reading, and makes me want to read more.

Thank you all for the feedback (last year, now *cringe*). I'm finally getting this sucker ready, so here's my most current pitch. Just in case I need it for a RevPit teaser.

I can't get into the theory as it's too complicated for submission material and the why for the sacrifice isn't answered until the climax, so that's not really something I can use in a pitch other than stating it's for the planet to have another quarter-century of prosperity--but I am at my wordcount limit with this pitch so I'm not sure how to add that in.

When a moss-like rash appears on Ren, marking her as the next human sacrifice, the single-mother must become a fugitive to prove a radical new theory that the sacrifices for her man-made planet are worthless. If she can't, she'll never see her son grow up #mockpit #A #SFY

I like the pitch but I don't feel that I know the story well enough. Why is there a sacrifice? I want to know more about the theory, too. Good luck!

When the mark of the next offering, a moss-like rash, appears on Ren's ______, She must choose between raising her son and becoming the next human sacrifice, a centuries-old tradition. The decision is easy, being a fugitive is not. But her radical new theory just might free the planet from _______. #mockpit #A #SFY

I took a swing at it. Hope this helps! There are a couple blanks that need to be filled. What do you think?

Thanks @Angela Super! I'm most drawn to the second one, I think. I see what you mean about sticking to the character + plot/conflict + stakes. I'll be back once I think a little more

The biggest issue is we don't know why there is a human sacrifice to the planet. You need to be super specific about the whys and hows in a pitch without getting too world-buildy and this may prove a little difficult with your story. Since I know a little bit about your book (y'all should read her query to become familiar!), let me brain on a couple alternatives for you:

Single-mother Ren discovers she's the next offering in a centuries-old tradition of sacrifice to the planet. She becomes a fugitive to prove the sacrifices are unnecessary. If she doesn't, she'll lose her son, and her life. #mockpit #A #SF #SFY

or

After discovering she's the next sacrifice in a centuries-old planetary tradition, single-mother Ren becomes a fugitive to prove the sacrifices are worthless. If not, she'll never see her son again. #mockpit #A #SF #SFY

The idea is to present your character + plot/conflict + stakes. If you can spare the space for some voicey bits (like in the second option... There's plenty of room to do a little futzing.), then use it if you want. If you don't... I AM noticing a trend toward shorter pitches happening during pitch events.