Goofs

(at around 1h 10 mins) When Bruno drinks the formula and shrinks, his clothes shrink right along with him.

(at around 1h 26 mins) The Swamp Thing performs his veggie-magic healing trick on Cable, curing her wound where she was stabbed. Remarkably, those pesky blood stains on her shirt also vanish.

(at around 30 mins) When Swamp Thing first appears, he grabs Ferret and yanks him into the water, totally submerging and soaking him (including his head). A minute or two later Ferret's head is dry.

(at around 32 mins) The first time Arcane's thugs chase Alice Cable in the swamp, one of the guys shoots his own man and the squad leader takes his rifle away from him. After a quick cut away, the original shooter has his rifle back.

The Swamp Thing smashes the Chevy Blazer chasing Alice down the road but when she looks at it afterwards with Jude, it's a smashed IH Scout.

(at around 43 mins) When Jude and Cable are discussing the "tree" that Arkan's men's truck ran into, they look down at Swamp Thing's footprint and a white pointed toe shoe is clearly in the shot. However Cable and Jude are wearing black shoes.

When Swamp Thing rips off the roof of a car, the way it goes up in the air makes it obvious that the roof is being pulled up by a cable.

(at around 36 mins) When Cable gets to the pay phone, the sound that's heard after she puts her money in the phone, is the sound that the phone company used to play when a phone had been left off the hook. The use of the sound dates back to the 1950's and 60's. It has since been discontinued.

(at around 57 mins) In the scene before the Swamp Thing heals Jude, he walks by a very large bush that is clearly camouflage netting.

When Swamp Thing first saves Cable, two of the commandos have suspension lines attached, one clear and later one black, to pull the men up when Swamp Thing throws them.