Extras and outtakes are usually part of longer compilation videos.
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Kenny dressed Spenny up as a clown and urinated on him while he was unconscious.
During the episode Spenny couldn't handle his own brain, so did what all addicts do, and took drugs to deal with his problems. Not only did he steal the drugs from his Mom, that he described as tranquilizers, he then got wasted, likely due to mixing it with his alcoholism, as was evident by Kenny testing it wasn't alcohol when he had a sip, and eventually passed out. At this point he was lovingly taken to bed, put in a clown costume, and urinated on. All of these were illegal humiliations.
26th Dec 2005 / Season 2 Episode 12
Kenny disguised apparently mean acts as "nice", such as giving Spenny the gift of a parrot to annoy him. The two assigned a referee after agreeing they would never concur on whether an act was mean. After Kenny pretended to have slept with one of Spenny's previous girlfriends when they were dating, Spenny then consumed several tranquilizers in a final effort to prevent himself from being mean. Spenny eventually passed out until the end of the competition.
In Mean, there was a hilarious scene where Spenny jumped on an inflatable punching bag with Kenny's face printed out, and wounded himself. In Basketball, Kenny has who Spenny referred to as his "wheelies", beat up and run over an inflastable doll with a Spenny face printed on it.
Endurance competitions entail lasting longer than the other guy. They include competitions when the other guy might get caught or break a rule first, as they didn't endure longer.