Monster Rancher

**Note**: When monsters are killed, they become lost discs. When Moo is defeated the first time at the end of Season 2, the lost discs are turned back into Mystery Discs that can once again be unlocked, reviving that monster. This list will specify those that are unlocked again by Season 3.

### Season 1

* Captain Black Dino - Sent falling into a raging river below by Genki
* Captain Jell - Punched by Golem
* Unfortunate Jell - Punched by Golem
* Seed Sisters - One was killed by Genki catapulting a boulder at her, the other two were killed offscreen by Alan
* Captain Dino - Slashed by Tiger with his claws
* Captain Kuro - Tackled over a cliff by Ed and fell to his death. Is unlikely to be unlocked again
* Captain Clay - Killed by Pixie with Lightning
* Gooji - Punched into a whirlpool by Golem. Is unlikely to be unlocked again
* Joker - Killed by Hare with Dragon Kick
* Captain Scaled Jell - Killed by Pixie with Torpedo
* Gali - Killed by Mocchi with Mocchi Cannon. Was later resurrected purified
* Captain Black Worm - Killed by Tiger with Lightning
* Undine - Jumped into the fire. Redeemed
* Captain Jaggernaut - Killed by Melcarba with a spin attack
* Melcarba - Lightning rod stuck in his head by Genki causing him to be struck by lightning. Did not become a lost disc due to being an android rather than a monster

### Season 2

* Gray Wolf - Stabbed in the throat by Tiger with his horn. Redeemed at the last second; Was later resurrected
* Cabalos - Thrown out the window and over a cliff by Naga
* Stone Dragon - Sent falling into a bottomless swamp by Color Pandora with a Pinwheel Fireworks attack. Unlikely to be unlocked again
* Captain Arrowhead - Crushed by Jim with his ship
* Bajarl - Crushed by a rock formation sent falling by Holly detonating explosives
* Naga - While hanging onto the edge of his castle due to Mocchi's attack, let go and fell to his death. Was later resurrected purified
* End Bringer - Kicked over a cliff by Genki
* Chariot - Killed by Baku in a beam struggle
* Metal Jell - Killed in explosion of factory caused by the Knight Mocchi hitting the factory's devices and causing an electrical surge
* Evil Hare - Killed by Tiger with Lightning
* Renocraft - Killed by Suezo, Golem, Tiger, and Hare with Tail Whip, Tornado, Lightning, and Dragon Kick
* Captain Weed - Killed when Lilim sent his Seed Machine Gun back at him by snapping her fingers
* Captain Gangster - Stabbed in his weak spot by Captain Weed
* Lilim - Stabbed offscreen by Durahan
* Evil General Durahan - Killed when his former troops (now loyal to Moo) shot down his ship, which crashed and exploded. Was later resurrected; unlike Gali, Gray Wolf, and Naga, remained evil until his redemption in the final episode
* Weed messenger - Killed when Moo destroyed his ship with a breath blast
* Big Blue - Sacrificed himself to fuse with Pixie, turning her into Granity and healing her from the fight with Moo. Redeemed; With no body left, did not become a Lost Disc

### Season 3

* Captain Jelly Gaboo - Killed by Mocchi with Mocchi Cannon
* **Moo** - Destroyed by the Phoenix (now a fusion of Mocchi, Suezo, Golem, Tiger, Hare, Genki, Holly, Holly's father, Durahan, Poison, Mum Mew, Gobi, and Weed) charging into him. Explodes in a shower of rainbow particles, never to return.