So when I use a pup toy on my pupper he only gets Luck, nothing else. Each pup toy has been different (feathers, femur bone, box turtle, worm, etc.) His Luck stat isn't maxed out so I'm still receiving the cp, I'm just wondering why I'm not getting other cp points besides Luck.

Yup, I just used three different pup toys on my upper and I'm still only getting Luck.

I don't think that this is a bug but correct me if I'm wrong ( running on low sleep here xD)
With pup toys I've noticed that the CP goes to the lowest attribute first , so if you're pup has low luck it will go to that first and once it's high enough it should start going elsewhere.

Have you tried it with other pups? Cause Starwolfs comment may make sense, since pup toys are there to help so they may focus on lowest attribute or one that is very low

I only have one pup currently but I have more on the way. His current Luck stat is at 60 and not nearly the lowest cp stat. Pup
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Before him I had no issue with the pup toys giving only one stat. Once my other pups get born (and if I keep one) I'll check to see if the pup toys keep giving me only one stat.

Just tested with my pup, https://wolfplaygame.com/wolf.php?id=5175958

Used 2 feathers and 1 femur bone, got luck perception and stealth(Only had the 1 dom CP before pup toys)