Head Cannon thought
Ok was thinking about this. Always liked the idea of the grub scars, adding a bit of color and details on the body. But only ever seen 4 when there's 6 legs. And reading elsewhere how the top two grew into arms, but then wouldn't they only have 2 scars since the bottom two should become the legs? Then also the lack of bellybutton makes sense since they don't go through birth and no umbilical cord. But then they shouldn't have nipples either since nipples are for dispensing milk for the babby and they don't do that either (yes this would mean boobs don't make sense either but boobs are nice so...) So I did this quick sketch of what I think a troll body looks like naked, top two scars basically taking the place of nipples, with bottom two remaining the same, and the grub development isn't some cocoon or anything just there limbs slowly growing out of there bodies, there claw legs slowly becoming more and more useless as they just fuse to the body as the nubs become more flipper like and then growing into limbs. Then the claws eventually fall off the body like baby teeth leaving the scars behind.
