Other mistake: After the Grinch steals everything from the first house, when he drops all the bags on Max, the ties around the bags change from light brown to dark brown twice. Additionally, the bags ever so slightly change position the second time it happens.
Other mistake: When the Grinch slides down the chimney to the first house, part of his Santa suit and his hat flash green repeatedly.
Continuity mistake: At the end when the sled full of Christmas stuff is on the mountaintop, it starts sliding off the edge. It's going fast enough that it should be long gone by the time the Grinch reaches it, but when he does it's still right near the top of the mountain.
Revealing mistake: When the Grinch is cutting Max's antler, the cut lines appear on the prongs before he actually starts to cut.
Other mistake: When the Grinch is cutting Max's antler, the pieces that have fallen on the floor suddenly jump several inches closer to Max.
Continuity mistake: When the Grinch puts the antler on Max's head it has five prongs. But when Max tips forward, one of the prongs disappears as it's hidden behind his body. The Grinch only cuts off four prongs, but when Max goes upright again, the fifth prong is still gone.
Continuity mistake: When the Grinch has his change of heart, his eyes change from red to blue. However, when he looks up and sees that the sled is about to fall, his eyes are red again. When he's running uphill, they're back to blue.
Suggested correction: His eyes turned red again because he was afraid that the sleigh would fall. After he finds the strength to pull the sleigh back up, his eyes turn blue again.
While it's true his eyes go back to red when he sees the sleigh about to fall, when he's running after it, they're back to blue. They switch back and forth. And you can tell they're suppose to be blue because the part around it is white (the sclera if you will) instead of yellow.
I still think it's a creative choice showing his determination. When he sees the sleigh about to fall, his eyes turn red, they turn blue again when grabs Max, turn red again when the rope holding Max breaks, turn back to blue as he races after it, turn back to red when he realises it's too heavy, and finally go back to blue and stay that way when he finds the strength to pull it up. It's pretty consistent with his emotions in each shot. His eyes are only red during the parts where he isn't determined (and during the parts earlier when he's evil).
Continuity mistake: When the Grinch goes into the first house, you can see the Christmas tree in the background and it has a silver star on top. But later when he steals the star, it's gold.
Revealing mistake: When the Grinch hits the Christmas decoration with the cue stick, the ball rolls over the Christmas tree, not under.
Suggested correction: The Grinch picks up the cane, then hits the Christmas ornament with it. The ornament goes past the Christmas tree (in front of it), then knocks the other ornaments off the tree. What is the mistake? The ornament is not supposed to go behind or "under" the tree.
The green branches (i.e. the tree) that the ornament passes over are several inches off the ground, and therefore it shouldn't have rolled over them since it's supposed to be on the ground. In the next shot, we see the ornament rolling on the ground, where it is rolling under the branches before hitting the base and jumping up the tree.
You are correct. I first thought the mistake was talking about a layering issue, where the ornament was supposed to be layered behind the tree, or something. I'm not sure how I misunderstood that, but nonetheless, you're right.
Other mistake: When the Grinch tells Cindy Lou Who, "I'll fix it up there, then I'll bring it back here," when he says the word "back," his right cheek briefly turns white. Then, when he says the word "here," part of his left sleeve briefly turns green.
Other mistake: After the Grinch sends Cindy Lou Who to bed and closes the door, part of his Santa suit becomes the same colour as the background mid-shot.
Continuity mistake: When the Grinch tries to stuff the tree up the chimney, an ornament falls off the tree and rolls over to Cindy Lou Who's bed. Then, when the Grinch turns around to see Cindy Lou Who holding the ornament, it has grown tremendously in size.
Other mistake: When the Grinch runs to the top of Mount Crumpit and grabs the sleigh, a part of the sleigh disappears for a frame or two.
Other mistake: When the Grinch rides his sleigh back to Whoville and returns everything, as the narrator says, "He brought back their pantookas," a pink ornament lands on the Christmas tree, then changes to yellow mid-shot.
Continuity mistake: Max's antler changes constantly after being cut. The number of cut branches, the size, and locations all changes at various times. At first, it's 4 cut branches. Then when he jumps on the sleigh it's 3, and when he's hooked up to the sleigh, it's just 2.