That might be an issue with the game itself, Im not sure why it would be doing that :(
One thing that could potentially fix it is to narrow down the search? Maybe add in some traits you'd like to see in breedable lionesses? Test it out and see if that helps! I dont recall ever having problems when searching for reverse breedings with specified traits c:

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If it continues to be a problem, make sure to post it to the bug board so mods/admins can fix it in an upcoming bug fix update!

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i did enter some bases and mutations, i just wasn't sure they'd have much of an effect

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this is also happening on my side. not sure if this search link will work, as an example: https://www.lioden.com/search.php?s=lions&name=&owner=&lionid=&personality=&gender=&level_type=min&level=&flevel=min&fertility=&heat=1&age_min=&age_max=&sb_fee_stud=&sb_fee_breed=&gb_fee_stud=&gb_fee_breed=&for_breeding=1&mane=&mc=&eyes=&skin=&basecolor=86%21176%2181%21204%21161%21182%21169%21160&basegroup=&baseshade=&basegradient=&baserarity=&mutation=&mk_cg=&cg_slots=&mk_tg=&tg_slots=&tmo=&tm=&mk1=&mk1s=&mk2=&mk2s=&mk3=&mk3s=&mk4=&mk4s=&mk5=&mk5s=&stattype=min&str=&spd=&sma=&skl=&agi=&stats=&ac=Search#results

i am looking for lionesses that i can combo breed with my king's ebony base. of the 8 results, only 2 of them are in heat. and yes, the "In Heat?" box is checked.

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