Ensign Boimler reads the scenario's title.
Borg Encounter was one of the holopod simulations presented by Shari yn Yem during the drills she conducted aboard the USS Cerritos in 2381. According to Yem, the simulation was based on the experiences of various other Starfleet crews.
In the simulation, the occupant was placed aboard a Borg cube and tasked with evading the Borg.
When he was assigned the program, Ensign Brad Boimler figured it would be easy to complete, as he had "read literally everything about the Borg." Indeed, he successfully evaded the drones, climbed through a ventilation shaft and escaped the cube aboard a Borg sphere. To his disappointment, he only got a 79%, prompting him to try again. His subsequent runs had him rescue infant Borg, rescue adult Borg drones, call in a Starfleet runabout, and casually destroy the Borg cube. Unbeknownst to him and the rest of the Cerritos' crew, this simulation had actually been rigged by Yem for the odds to be much more heavily stacked against the user than normal, as were all the other simulations the crew had been given.
Boimler eventually achieved a perfect score, and reported to Captain Carol Freeman that he beat the Borg Queen in chess and taught her empathy, before he was forced to continue the test so Freeman could force Yem to change their scores upon learning of her plot.
Boimler was subsequently captured by the Borg once he was no longer able to evade them and assimilated, becoming Excretus of Borg before the crew freed him from the holopod. Upon asking deliriously if he had passed perfectly, Ensign D'Vana Tendi lied, saying he had despite the score reading 8%. (LD: "I, Excretus")
This simulation contains elements inspired by the events of TNG: "Q Who", "The Best of Both Worlds" (including background music from that episode), and Star Trek: First Contact.