I've noticed the length of the Red Death is listed at 510 feet long, 155.4 meters. While it and the Bewilderbeast are both very large, I would like to know if this is the offical numbers or an estimate. These numbers seem a bit on the large side for the shown length of the Dragons. Given the 6'1" individual put next to it for scale, and quick comparision by comparison the dragon would be about 50 feet tall and about 160 feet in length, still large, but not near the length given in the artical infobox.
Addtionally, in the Movie, we see Fishlegs and Snotlout in close proximity to the Red Death's head. Given thier height, the Red Death's head is proably about 25 feet tall from the lowest point of the chin to the highest point on the crown. This given with the size of it's head in comparison to the rest of the animal, means it is virtully impossibly for it to be 99 feet tall. I've taken the liberity of taking the size comparison picture and showing how many humans tall and long the animal is.
The long and the short of it is I really don't feel the current mesurments are accurate.
size mesurment