Game two of the Fischer-Spassky world championship in 1972 comes to mind. Fischer forfeited it because of the cameras in the main hall. Due to Fischer's theatrics, Spassky agreed to play the 3rd game away from the audience, and lost. Then the drama by the Soviets around "devices" allegedly placed in Fischer's chair designed to disrupt Spassky's thinking.
The entire Karpov-Korchnoi world championship match of '78 was wrapped in oddness including a Russian "psychic" whose image graced the cover of (then) Chess Life and Review. The Soviets sent the "psychic" strictly to unnerve Korchnoi who apparently believes in such things. Florencio Campomanes, the president of FIDE, allowed the psychic to sit in the first row, even after it was agreed he would not. Then there was the yogurt scandal, where the Soviet support staff sent the snack to Karpov without Karpov asking, raising protests from Korchnoi's team since the timing and type of yogurt could have been a coded message. Ah, and also Campomanes allowed Karpov an unscheduled break in the tournament so he could rest.