An earthquake wakes a Highbreed officer, who was put into stasis and only to be awakened if the Highbreed lost the war. Per his orders, he triggers a weapon of last resort meant to destroy Earth. Mind-controlling seeds take over Grandpa Max and five others, using them as the brain for a living bomb that will end all life on the planet. The Highbreed officer refuses to believe Ben's claims of peace and won't divulge how to stop the creature. While Gwen and Kevin try to slow it down, Ben enlists the aid of Reinrassic III to get the Highbreed officer to cooperate. Unable to stop the monster from the outside, Ben, Gwen and Kevin sneak inside the monster to destroy it within. They manage to save the human beings used as its brain and the Highbreed officer sacrifices himself to dispose of the creature safely.
After Seedling 2 reported in, Seedling 3 (via Max Tennyson) reported to the Highbreed that five Seedlings were present. However, when Max had shown up, four other Seedlings were already present and Seedling 2 did not show up until after Seedling 3 did, meaning that there were six Seedlings and not five.
When the Highbreed officer flew into the Highbreed Tree Monster, after the scene where they show Reinrassic III and the soldiers, the Highbreed officer was with them.
Humungousaur and the Highbreed Tree Monster's heights change throughout the episode.
When the Highbreed Tree Monster was about to fall down and the Highbreed officer ask Ben's team to gather all the people and get out, only Ben's team got out and they didn't gather all the people.
The Highbreed officer appears not to have been affected by the Omnitrix wave in War of the Worlds: Part 2. Of course, this may mean that not all Highbreeds' coloration or shape changed.