6_legs and 8_legs got implicated to multi_leg a few months back, without any discussion:
https://e621.net/tag_implications/29103
https://e621.net/tag_implications/29105

Which is problematic considering that multi_leg is for creatures with added legs. It doesn't apply to anthropoids and arachnids which naturally have 6/8 legs, and are currently getting incorrectly implicated as multi-leg.

One solution to this would be to leave *_legs tags for added legs only, and instead start tagging hexapod and octoped for creatures that naturally have that number of legs. As we already do with other creatures: biped instead of 2_legs, quadruped instead of 4_legs.

Why 'hexapod' when the rest of the tags ('biped', 'quadruped', 'octoped') end in -ped? Because the latter are all Latin, whereas 'hexapod' is Greek. Hexapod has become commonplace in regular usage, likely because some people find the Latin 'sexiped' to be a bit embarrassing to say.

Any opinions? Alternate solutions?

I've removed the implications for 6 and 8 legs as a start.