When this Dirty Trick is called, the opposing team's coolers are spiked with psychedelic drugs. When the ball is snapped, the effect kicks in, creating three symptoms:
The view is distorted with weird colors, and psychedelic rock music plays in the background.
The game plays in slow motion.
All controls for the offense are reversed.
The effect lasts for a limited time unless the play ends early. Once the effect wears off, play continues normally.
Description from the Official Game Manual:
The defense spikes the opposing teams Hateraid cooler and when the ball is snapped the screen turns psychedelic and all players move in slow motion. If that’s not enough, the offense also moves in reverse to controller input. For example, if the user moves the player forward he will go backward, if he moves the player left, he will go right. This effect lasts for a limited amount of time.
Strawberry Fields comes from the song Strawberry Fields Forever, written and originally performed by the Beatles but since covered by other artists. The song is considered a prominent example of the psychedelic rock genre and is very fitting with the overall psychedelic theme of the Mile High Chronic.
This Dirty Trick is similar to making contact or eating a Fuzzy in Super Mario World 2: Yoshi's Island and it's remake, Yoshi's Island: Super Mario Advance 3.