I know some of the cards were reworded or changed slightly for the second edition, but are there any cards that were outright removed for the second edition?
The closest was Monster Batteries was remade into Battery Monster. It's still the same basic effect (pay energy now, get more energy later) but the card is actually worth buying now.
A few had the name change for some reason, but the effect is still the same.
All the other changes are just clarifications.