Dinosaur King: Mesozoic Meltdown (also known as Pterosaur Legends in the Japanese version) is the second season of Dinosaur King. Despite being billed as "Dinosaur King: Mesozoic Meltdown" in 4Kids commercials leading up to its debut, neither the name nor theme song was changed during the actual episodes and the name was never used again after the season started airing. This season highlights the D-Team and Alpha Gang working together against the Spectral Space Pirates, a group of alien time-travelers who wish to destroy and control time and space by getting ahold of the Seven Cosmos Stones. Unlike the episodic first season, this season is split into a series of 4-episode arcs, each one in a different place and time in history.
Series 1 can be found at Dinosaur King Series 1.
As of late 2014, all Dinosaur King episodes have been removed from Hulu, and most have been listed as Private (unviewable by the public) or as only available in certain regions on 4Kids' YouTube channel, save a few random episodes from the first and second series.
Rex Owen and the Alpha Gang have barely even left Max and Zoe when they come right back! Rex reveals that they returned to the past because they were attacked by unknown forces (later revealed to be the Spectral Space Pirates). While Max and Zoe tour the (now slightly damaged) Backlander and get a glimpse of their new Dino Holders, the adults are kidnapped by the same forces that chased Rex!
With the help of Dr. Z, the Backlander is repaired, but goes flying off into the time-space vortex with no destination! Racing uncontrollably through time, the D-Team and Alpha Gang encounter and are led by a mysterious birdlike being known as the Pterosaur to numerous places and time periods of Earth's past, as they fight the Spectral Space Pirates, who use dinosaurs equipped with powerful Spectral Armor, for control of the 7 Cosmos Stones, glowing gemstones that have enough power to control or destroy the entire universe, every dimension, and all of time-space ten times over! The battle for the fate of the Universe has begun . . .