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Continuity mistake: As Sid says "Yeah. She's tons of fun and you're no fun at all", Diego is on the right side of Sid (from Sid's point of view), standing relatively close beside him. Immediately in the next shot, when Sid finishes off by saying: "She completes you", Diego no longer can be seen beside him. (00:34:45)

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Other mistake: Watching the green fish monster closing up to Sid and Diego, viewing the monster from underneath it, it would have taken approximately only one second for it to have reached them in the rate it was displayed traveling at (considering as of the end of that shot). But it only reaches them about eleven seconds later. (00:31:05)

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Continuity mistake: As Manfred and Diego tells Sid to stop singing the vultures' song, Crash and Eddie are standing upon Ellie's tusks. In the following shot, the possums are not there. (00:58:35)

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