"Accounting for Lawyers": Pierce embarrasses Jeff at a party at his old law firm Hamish, Hamish & Hamlin by knocking over a table filled with champagne glasses.
"The Psychology of Letting Go": Jeff tries to prove Pierce's religion is a fraud by attempting to force him to deal with his mother's death.
"Basic Rocket Science": In the The Eleven Herbs & Space Experience, Jeff scolds Pierce for talking to S.A.N.D.E.R.S. and then tries to stop him from destroying the TV unit.
"Aerodynamics of Gender": Pierce discovers Jeff and Troy's secret trampoline and ruins it for them.
"Asian Population Studies": Pierce opposes Jeff who wants Chang to join the study group. Pierce wants to have Rich (and his kettle corn) join. After Jeff wins, Pierce says Jeff has hurt the study group in a way that will never heal.
"Advanced Dungeons & Dragons": Jeff threatens to kick Pierce out of the study group for not co-operating in the D&D game with Neil.
"Early 21st Century Romanticism": Jeff chooses to ignore the warning signs that Pierce is overdosing on his pain medication.
"Intermediate Documentary Filmmaking": Faking that he is on his death bed, Pierce orchestrates revenge on the study group for disrespecting him by playing mind games with them and tells Jeff he has located his father William Winger.
"Competitive Wine Tasting": Jeff is shocked when a beautiful woman he hits on in wine class chooses Pierce over him.
"A Fistful of Paintballs": In a flashback to events prior to the paintball competition it's shown that Jeff and the study group voted on whether or not Pierce would be allowed to return to the group the next semester.
"For A Few Paintballs More": Pierce emerges the victor of the paintball war winning the prize money for Greendale. Jeff and the rest of the study group offer to forgive his previous actions and let him back into the group but he refuses saying he is done with them.