This episode starts out with the tallest naming off some of the stuff that Zim requested for his mission. One of them being a sack of toquitos, and GIR asked if they got his toquitos yet. Red told him that his mission was to ovserve the planet, not to annhilate it, and Zim said that he was good at it though, and Purple said that he'd love to grant his request, but he's insane, er... untrained. Red agreed and said that he's an untrained invader, and battle tanks are for hardened soldiers. Purple got the idea to send him to Hobo 13, the finest military training planet ever, and there he would be (torn limb from limb) evaluated as a soldier, and if he passes, they'll send him a big bag of battle tanks. Zim told them thank you and signed off.
On Hobo 13, Zim said that with his mighty fists of horror and unstoppable cruelty, he is the tool of destruction, vengence, and fury. Hobo 678 told him that he only asked for his name, and went on to the next people. Throbulator: a creature of pure headache, Invader Skoodge, and Zim said he thought the Almighty Tallest killed him, he said yeah, but he's ok now, and the tallest would promote him if he passed the evaluation. Zim called him foolish and gullible. Hobo 678 told them that they must choose a leader, and Zim said that he chose himself, and anyone who objects will taste his vengecne and revolting power. Hobo 678 told them that they will go through a series of tests, and at the finish line is is the dreaded fortress of pain, and any mistakes and they will be pinned away to a loosers holding pin, and a guy eating a sandwhich was zapped away. The tallests were watching this, saying that they can see that Zim has begun his journey to the Fortress of Pain, and asked if anyone wanted to bet that he'd get blown up. A man bet 1,000 moneys that he would be eaten, and another guy bet 2,000 moneys he would be chopped in half. Red told Purple that if no one bets on Zim, they could be out a lot of moneys, and Purple asked if anyone bet on Zim succeeding, and when no one did, Red made the servent drone Bob bet 500,000 moneys on Zim succeeding, and the guy said that he only makes 5 moneys every two years, but Purple made him bet.
Their first task was to cross the molten pit of hideous screaming pain, and their power suite will provide them with some protection, but nothing will protect them from a stupid mistake, and Hobo 678 jumped the pit to watch them. Zim said that they will stand on each others shoulders and fall forward, creating a bridge and then helping each other to safety, but one guy asked why they don't cut a tree down and use it as a bridge, it's safer, and everyone agreed, except Zim. He asked him if they were going to have trouble, and they ended up making the human bridge instead. Zim pushed them forward, and they fell, and he walked across by them. Three people fell and went to the Holding Pin of Pain, and Zim yelled victory. The tallest saw this and said that is shouldn't have happened, while Servant Drone Bob was counting his moneys.
Hobo 678 tells them that they are at the Stinking Canyon of the Meat Thursty Hogulous, and he throws a piece of meat into the canyon. Their test is to navigate to their end all the way over to the other end, alive. Zim said that he had a plan, but he needed a volounteer to distract the hog beast, and Skoodge voulenteered, and Zim pushed him in the canyon. The hogulous started chasing Skoodge, and Zim told them to move on. They make it to the other end, and Zim says it's another victory, but Hobo 678 asked about Skoodge. Zim told him that's what he would've wanted, but then thought about it, said oh no!, and tried to pick up a boulder, but it wouldn't budge. Zim decides to steal energy from the rest of the team. He said that with enough energy, he could lift up the boulder and throw it at the monster, so no one would say that he tried. The energy thing was taking awhile, so Zim said that he tried, and that the Fortress of Pain awaits. The tallest are still watching this, and Bob said that if Zim finishes, he gets 6 Million Moneys. Purple said that he needed a refil, and Bob told him to get it himself.
Back on Hobo 13, Zim and his team are running through a wall full of lasers, making it out with one less person. They had more tests, each one losing at least one soldier. The last test, he lost three more, ending up with just one more soldier. Zim and Throbulator make it to the Fortress of Pain, a giant building with giant needles sticking out of it. Zim uses Trobulator to barge open the doors, and when he finally did, Throbulator's head burts open and he died. Inside the Fortress of Pain, 678 tells him that all of his team has gone, and that he is a disgrace to Hobo 13. Zim tells him that he must have the tanks or he won't get them, and 678 told him to fight him. A ring appeared around them, and 678 told him that it was a transportation field, and the loser gets sent to the Outhouse of Madness because the the Holding Pin of Pain was full. The fight, and 678 has Zim by the head in the transportation field. Zim is stealing energy from 678, but he doesn't know it, and Zim punches him, knocking him out of the ring, and Skoodge comes in telling Zim that he escaped the canyon, but is squished by 678. The Hogulous comes and bites down on 678's head, and 678 hit him with Skoodge, but it doesn't do any good, and 678 is carried off by the mouth of the Hogulous.
Bob tells them that they can serve themselves from now on, and they give Zim a ship instead of the tanks, with the controls locked on to the sun, and Bob tied down in the ship.