If he gets out of hand, print this >> https://www.prusaprinters.org/prints/2687-spider-splatter

I made a new version that fixes the problem with the joints wearing out quickly. I redesigned the sockets so they are more flexible and should maintain a snug fit.
https://www.prusaprinters.org/prints/2690-wolf-spider-v2

I tried to make this with minimal supports (the supports required are already in the .stl files).
I have printed this in ABS and PLA and both work great without adjustments.

You need to print the following:

4 - LegTipLong.stl (front and back)
4 - LegTipShort.stl (middle 2)
2 - LegMedium.stl (back)
6 - LegLong.stl (front and middle 2)
8 - LegShort.stl (attach to the body)
2 - Fang.stl
1 - Head.stl
1 - Abdomen.stl -or- AbdomenFangs.stl

Print instructions

I recommend printing this in ABS (or some other soft plastic). I gave the one I printed in PLA to my daughter. The joints seem stiffer at first and wear out very quickly, becoming loose and sloppy. The ABS one moves more smoothly and doesn't seem to wear out as fast.
Update
Fixed in new version here: https://www.prusaprinters.org/prints/2690-wolf-spider-v2