Here's my favorite Done-In-One characters as much as I missed them,
The Trollogs/the Giantorrs/Plutar/Burn-Out/boar king/two Bolkins/The gargoyles/Ta-She/The Inflamer/Mongor/Nemex/Brodo/Tartara/The Demolisher/Char-Ninn/The Mad Bubbler/Two-Time/Frogman/Shadowmaster/Zaxx(Thundercats) - All of them were awesome one-shot characters especially the villains that were more cooler/interesting than the Mutants & Mumm-Ra.It was so cool that the Inflamer/Mad Bubbler were two of the best one-shot villains to not get a comeuppance at the end which was great.
Major Courage/Djinni/Fritter O' Way/Circe/The Space Microducks/Ripcord,Birdy,& Loopy/Bomber/Skittles the penguin/Jungle Duck/Feathers Galore/Gruta/The Amazon Queen/Count Roy/Cinnamon Teal/Robotica/The Beagle Babes/Sen-Sen(Ducktales) - They were all fantastic one-shot characters while both Circe, Loopy, Feathers, The Amazon Queen, & Cinnamon were my one-shot childhood crushes when I was young since they were pretty hot/interesting:anime:.
Chewcudda/Marcia Martian/Danforth & Margo Mallard/Witch Sandy/Lightning Rodriguez/the mosquito/Sappy Stanley/Blard Simpleton/The Roches/Foxy & Roxy/Julie Bruin/Vinnie the deer/The Coyote Kid(Tiny Toon Adventures) - All of them were great/hilarious Done-In-One characters which they have alot of wacky potential in their characters.
Anemia & Iodine/Little Freaks/Louie & Louie/Fuzzball(KaBlam!) - All of them were pretty awesome one-shot characters in that great show which Anemia was the coolest/hottest catgirl character ever and Louie & Louie were so hilarious, ahh, the memories.
The Star Rovers(Road Rovers) - The most awesome one-shot characters ever who're a
Star Trek-themed dog crew along with the hot female dog captain who's the second hottest after Colleen.
The Evil Stan,Kyle,& Eric(bearded kids)/Ugly Bob/Mark & Rebecca the homeschool kids/Tom & Mary/The New York Kids/Scuzzlebutt/Jakov & Hope/Kelly(Kenny's girlfriend)/Larry the frozen man/Dr.Adams/The Romanian Quintuplets/the four Afganistan boys/Mark & Lisa/Sister Anne/the FBI Kids/Romper Stomper/Haman/Zitar/the evil towel/The Earth Day psychopaths/the rich black kids/Bill Cosby the cyborg/Josh/Tad/the Visitor Leader(talking taco)/the future people/The Aging Hippie Liberal/The Cripples/The Bloods/Gary & the Harris Family/Chief Runs With Promise & the Native Americans/Alex Glick/The Orange County Kids & their coach/Nancy(Jimmy's girlfriend)/Blanket/the Chinese Mafia/the Fort Collins Kids/the Denver Kids/Bat Dad/the Adams County coach & his Pee-Wee hockey team/Thomas/Patty Nelson/Bradley(Leopold or Butters' camp friend)/the Ugly Kids/Travis the louse/Bahir Hassam Abdul Hakeem/Bridon/Thad Jarvis/the Vampire Kids/Hollis & his son/Babyfarts & the two alien policemen/Sally/Mike the weird kid/Casey Miller/Billy Miller/Kip Drory/Profile Stan Marsh/Theresa and her family/the New Jersey jerkholes/Dr.Chinstrap/Mr.Yelmac/Billy/Evil Woodsey the Owl/The Geniuses,Leslie/Kelly/Funnybot/The Canadian prince and princess/The Mushroom Canadians/RUSH/The Native Canadians/Tooth Decay(South Park) - All of them were awesome/hilarious Done-In-One characters as much as I loved their episodes involving their characters which the Evil Eric Cartman was Eric's cool/nice doppelganger, Jakov & Hope were hilarious, the Romanian Quintuplets were so adorable, Zitar was the coolest alien villain ever, that evil towel was awesome, but sad that he died, Casey Miller was such a funny one-time character, & Profile Stan Marsh was a pretty awesome huge scary evil twin ever

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Keef/the alien babies/the Planet Jackers/Iggins(Clarence Wong)/the rat people/the Mysterious Mysteries anchor/the Blotch/Yoa/Meelina/Rob/Alexi/two dumb aliens(Zim's kidnappers)/Tak & MiMi(Invader ZIM) - That epic Nicktoon had their great cast of weird/wacky/interesting Done-In-One characters, but I so miss Keef, the Planet Jackers, & Tak/MiMi though, they were so cool with alot of potential.
The Commander of Darkness/the evil tyrannosaurus rex(Hero:108) - They were pretty cool one-shot villains which the Commander of Darkness was such a hilarious cowardly villain, hahahahahaha.
Doomsmane/Skulldozer/Addversarious/Boaconda/Cranky Doodle Craw Daddy/Big Bone/Crabman/Sharkman/Spikeman/Hoffman/Mean Marine/Mr.Peel/Bobby Wasabi/Baronus(Ultimate Muscle:The Kinnikuman Legacy) - All of them were pretty cool/interesting one-shot villains with great designs from that awesome comedy wrestling anime, but sad that the two d.M.p. bosses, Doomsmane & Skulldozer won't used more after their deaths since they were awesome threatening villains.Mr.Peel being a giant talking banana with a Jamacian accent is the most hilarious idea ever, hahahahaha.
A-20/the Grunty Girl/Subaru's evil player killer doppelganger(.hack//SIGN) - All of them were great/interesting one-shot characters which A-20 was the cutest noseless girl character ever & Subaru's evil player killer doppelganger was a pretty hot one-shot villainess.