He-Man/ThunderCats defeated villains and Cringer runs into He-Man's arms thrilled his best friend is alive. The three rush back to the ship desperate to get back to Eternia before it is too late. The four Ancient Spirits of Evil have arrived on the doorstep of Castle Grayskull while Skeletor and Mumm-Ra look on. Randor has assembled an army alongside the Thundercats and the combined heroes attack the giants. Man-At-Arms, Tygra, and Panthro assemble a cannon of combined Eternian and Thundarian tech to attack the Spirits while the others buy them time. Inside the Castle the Sorceress summons the Castle's defenses to
He-Man/ThunderCats shield it from attack when Jaga's spirit form arrives. Jaga tells the Sorceress that he believes there is a way to stop the Spirits but the answer lies on the Thundercat's destroyed home world of Thundara. The Sorceress opens a portal in space and time for Jaga and her to slip through and get the item they need. Outside, despite the hero's best efforts, the Spirits close in on Castle Grayskull. When Man-At-Arms, Tygra, and Panthro fire the cannon at one of the Spirit's head it simply laughs off the attempt and turns to attack the castle. Tygra then uses