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by Phil
Jun. 2, 2008 (3:07pm EST)
In the commercial Adult Swim is running, Billy already has his robotic hand during the flashback. Also, in the season three preview that Publick and Hammer put together, he's got it during the nozzle scene as well. So we may not actually find out how he got the hand...

In the title "The Invisible Hand" may refer to Phantom Limb...he calls himself The Invisible Hand in Showdown at Cremation Creek.