Dr. Slicer is a rather strict and militant teacher. He only appears in the episode "Prickly is Leaving". However, in his one appearance, he has gained a reputation for being rather disproportionately ruthless and cruel. He is addressed as a Doctor. He is a minor antagonist of the episode.
Nothing much is known about Dr. Slicer's past. It is stated he graduated from an unknown university with "a Ph.D in discipline with a minor in punishment." Moreover, he may have been in the military at some point considering his demeanor. He dislikes pranksters, or "funny boys," because according to him one gave him a scar during a prank involving electromagnets. When Principal Prickly accepts a job as the principal of a middle school, Dr. Slicer is hired to replace him at Third Street.
Dr. Slicer is a cruel, vindictive, strict, megalomaniac, and overly militant teacher who wants students to act like 'soldiers' and not like kids. He is very cruel, dislikes feelings and calls emotions sappiness, thinking that emotions make people weak. This makes him a (only marginally) family-friendly caricature of a Nazi general in many ways. It is interesting to note he bears a strong resemblance to Heinrich Himmler, further reinforcing this point. Whether this resemblance was intentional is unknown.
Dr. Slicer is the only villain in Recess series who can be called truly evil. He is openly antagonistic, cruel, villainous and unlike most adult antagonists, who have good intentions but use bad methods, he does not care about doing good for school and only wants power and control.
He’s said to resemble Heinrich Himmler, this much is obvious when one looks at his photograph. He’s bald, has glasses, a thin mustache, wears a suit with an overcoat, and a brown necktie with navy blue stripes.
When Prickly announced he was to leave to be the principal of a middle school, everyone rejoices, but then, Menlo gets a fax foretelling Slicer's arrival, and he informs The Recess Gang about him, thereafter.
Dr. Slicer arrives, and he immediately makes life miserable for the kids and staff for the brief time he's there. He makes T.J. wear paper hats that say Funny Boy and Captain Sappy, hands Finster's job to his assistant, and works to practically convert the school into a military base.
He had plans to tear down the jungle gym and put in a guard tower, clean the cannon kept in front of Third Street's gate to make it operational, and to make students wear uniforms and regulation haircuts. Expectantly, the gang makes various plans on different ways to stop Prickly from leaving. While they were unsuccessful at first, Prickly eventually decides to stay. The last we heard of Slicer is when he yelled Prickly was making a big mistake. It is unknown what happens to Slicer after this, but it is possible that he became principal of the middle school or was fired by the district for his actions.
- Dr. Slicer resembles Heinrich Himmler to some extent, arguably this is no accident.
- It is unknown if Slicer has ever been the principal in other schools, or what actually happened in those schools.
- Despite appearing in one episode, Dr. Slicer is possibly one of the cruelest character in the entire series, surpassing all other Recess antagonists. Even Miss Finster and the staff balk at his methods.
- He is surpassed in cruelty by Dr. Phillium Benedict who nearly went global to destroy recess.
- He has Ph.D. from an unknown university.
- Dr. Slicer could be a pseudonym.
- He is one of the few people to truly terrify T.J..He is also one of a few villains that T.J. himself did not defeat directly, he was only thwarted by Prickly deciding to keep his job (though that being said, T.J. was indirectly responsible for Prickly deciding to keep his job due to admitting he'll miss Prickly, as well as Slicer exposing his more notoriously cold personality in front of Prickly).
- Spinelli also was terrified of him, as she had no interest in standing up to him, which is remarkable considering she's stood up to many adults as well as King Bob in the first episode and bully Gelman later in the show's run, anyone who strikes that kind of fear into Spinelli‘s heart is bad news.
- Dr. Slicer is what's known as a Knight of Cerberus, named after Cerberus Syndrome, when a show takes a darker, much more serious turn.