does they appear in any other shows?
No, but they appeared in comic books and video games.
Plankton and Karen
The fourteenth issue of "SpongeBob Comics", titled "Plankton Comics," is centered around the Planktons and includes six original stories set at the Chum Bucket. The 2013 video game "" is Plankton-themed and features Lawrence and Jill Talley reprising their voice roles from the show as Plankton and Karen.
is plankton from spongebob a zooplankton or phytoplankton Plankton is an intellectual planktonic copepod and Karen is a waterproof supercomputer. they are voiced by whom in spongebob squarepants? Mr. Lawrence and Jill Talley what is its role in the series? Plankton shares a rivalry with Mr. Krabs, who owns the far more profitable Krusty Krab restaurant and sells a fictional burger called the Krabby Patty. Plankton and Karen often devise schemes to steal the secret Krabby Patty recipe, but their efforts are always thwarted by Krabs and his employees.
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Plankton and Karen [SEP] In other media
Plankton and Karen have been featured in various forms of "SpongeBob SquarePants" merchandise, including video games and action figures. In 2006, Ty Inc.'s Beanie Babies introduced a plush toy based on Plankton. A Lego building set based on the Chum Bucket, including a Plankton minifigure and his laboratory with Karen, was released in 2007. The fourteenth issue of "SpongeBob Comics", titled "Plankton Comics," is centered around the Planktons and includes six original stories set at the Chum Bucket. The 2013 video game "" is Plankton-themed and features Lawrence and Jill Talley reprising their voice roles from the show as Plankton and Karen.