|Season 1, Episode 4|
|Japanese Title|| 永遠のワーム|
|Episode 03: Guardian of the Disks||Episode 05: Tiger of the Wind|
Eternal Worm is the fourth episode of Season 1 of the Monster Rancher anime series. It aired in Japan on May 8, 1999.
Upon defeating the Baddies Genki and the gang obtain a new Mystery Disc. It is, however, quickly stolen by a boy named Alan. Genki and Mocchi run after him but find they need to fight his monster, Worm, first.
Now with a new ally on the team they can get further on there quest. The team is looking for another Mystery Disc but they don't have any luck on finding it. Mocchi complains that he is hungry so Golem picks him a plant with some food. While Suezo is arguing Mocchi bites into something hard... the Mystery Disc! Then a pink mist comes in the air and everyone falls asleep. Some of Moo's baddies, The Seed Sisters, try to steal the disc stone. Genki wakes up with a rude awakening with Mocchi falling on him. The baddies shoot seeds but Golem gets in the way and tells them to run. Suezo and Genki build a catapult and launch a giant boulder, it crushes 1 of the seed sisters turning it into a disc stone. Now the baddies retreat and the team heads to the shrine. While reviving the monster a boy steals it. Genki chases him out of the shrine. The boy calls his monster and the ground starts to tremble. His monster, Worm, comes out the ground. He commands and bosses his monster around. Golem saves Genki from being hurt and the boy escapes. Genki is mad at the kid for treating his monster badly. Genki finds the boy and yells at him about the way he treats his monster.
The boy says "You use monsters then you throw them away when your done". Then the 2 remaining Seed Sisters come. The boy tells them his name is Alan and he claims that he is going to join Moo. Alan throws a net over Genki and Suezo. The boy tricks Holly, Suezo, and Golem to believe that the Worm attacked him. He is about to give them the disc stone until Worm comes up out the ground and attacks. The sisters shoot there pollen making Golem fall asleep. Then he ties Holly and Suezo up with his whip. After they find out he was faking about turning good the Weeds grab the stone and his whip.
Alan finds out that they were using him. He tells Worm to attack them but Worn appears to be ignoring him for being cruel to him for so long. Worm sides with the Weeds and they order him attack Alan and the Gang. Worm now shoots needles at them. The needles cut the vines and there freed. The sisters attack Worm for disobeying but Genki kicks them in the face with his skates. Alan finally understands that Worn only did what he did becuase he had liked Alan as his friend, not his master. Alan says he's sorry to Worm and the weeds hit the both of them.
The sisters drain all of Worms life and Worm turns into a Lost Disc. They all attack the sisters and the sisters are destroyed. Alan is at Worm's disc crying with flowers. Alan thinks back and remembers all the good memories they had. The gang comes to him and gives him a baby Worm that they just unlocked. Alan cries in joy, as now he had opportunity to redeemed himself. They then continue on their quest.