Just out of curiosity.
✓ ANSWER ACCEPTED
Do negative parts show ingame?
2 answers
✓ Accepted answer
They do show in-game, unless they have been unioned to a block. If it is not unioned, the negating part will appear.
Yes, they do. http://i.imgur.com/Ug1Ggdh.png
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1 comment
If you mean a script to create a new 'Part' instance, and set it's Name property to a negative number, then yes, it will show in-game. :) But if not, then this is considered off-topic, as it is not relevant to .lua (or coding). :(