Borg shields are ineffective protection against projectile or melee weapons, and several have been defeated in this way, or through hand-to-hand combat.
On stardate 50984.3 the Borg faced their destruction after they invaded Species 8472's fluidic space with intent to assimilate this species. Unfortunately – for the Borg – Species 8472 DNA encoding was so dense that nanoprobes could not assimilate their cells. Species 8472 responded with an all out attack on the Borg.
Species 8472 were introduced in Star Trek: Voyager as the deadly aliens that scared the Borg Collective, impressing viewers with their CGI design. Captain Janeway formed an alliance with the Borg to combat the dangerous Species 8472, who had the ability to wipe out all life in their galaxy.
Species 8472 destroyed the invaders and proceeded to retaliate with an invasion of the Milky Way Galaxy, intending to purge it of what they considered inferior lifeforms.
However, Picard is able to break Jack out of the Borg Queen's control while the Enterprise destroys the Borg Cube and with it, the Borg Queen and all of the remaining Borg drones.
He was assimilated by the dying Borg Queen and named Võx. New technology added to modern Starfleet vessels allowed these new Borg to assimilate the ships in moments. Using a rebuilt USS Enterprise-D, the command crew of that vessel saved Jack and destroyed the remaining Borg, seemingly defeating them once and for all.
Likewise, the Federation's encounters with the Borg often go down to the wire as well. Some fans say the Borg's technology would make short work of the Dominion while others maintain that the Borg would be unable to assimilate the shape-shifting Founders.
While Picard was ultimately able to defeat them, the Borg were still considered a lethal threat throughout the galaxy. That changed significantly with the events of Star Trek: Voyager's final episode "Endgame," which set the stage for Picard's final showdown with his greatest enemy over two decades later.
Originally Answered: How did Janeway take the borg down? Janeway used a nano virus the Borg were years behind comprehending to wipe them, out. She infected herself, and allowed herself to be assimilated. Faking hiding using stealth tech she knew wasn't effective against the Borg.
Q seemed frightened of Guinan, telling Picard that she is "not what she appears to be," and that Picard should remove her from the Enterprise. Considering Q's abilities, it's unclear why he would be afraid of Guinan, and Star Trek has never offered a real explanation for Q's reaction.
Officially, the existence of a Borg homeworld is a hypothetical one as it has yet to be revealed in a canon Star Trek source. However, an identity for the Borg homeworld is given by the non-canon novel Lost Souls, which names it Arehaz.
Whilst the Borg are primarily a nomadic space-bearing race they do however occupy planets with a typical population of nine billion drones primarily for the purposes of strip-mining the planets of all natural resources.
The pathogen completely decimated the Borg Queen and left the entire Collective in ruins, and while Picard and the crew of the USS Enterprise-D dealt the final killing blow, it was Janeway who originally crippled the Collective permanently.
Summary. Admiral Janeway cameo considered for Picard Season 3, but showrunner Terry Matalas feared it would overshadow Seven of Nine's story. Seven of Nine's journey in Picard Season 3 was one of the best story arcs, starting as First Officer and ending as Captain of the Enterprise-G.
Warning: Spoilers for Star Trek: Prodigy Season 1, Episode 12 - "Let Sleeping Borg Lie"The Borg returned in Star Trek: Prodigy season 1, episode 12, and the cybernetic villains proved they have the power to potentially assimilate Star Trek: Deep Space Nine's Changelings.
It is fairly likely that they cannot, due to their shape-shifting nature, and their natural state of being not being corporal. However, they could still be destroyed fairly easily due to another shortcoming the Founders have against the Borg: a single point of failure.
Susanna Thompson played the Borg Queen during her other appearances in Voyager besides "Endgame", and the late Annie Wersching portrayed Picard season 2's alternate timeline Queen. Once Agnes Jurati and the Borg Queen merged, Alison Pill took over the role in Picard season 2.
Tuvok, B'Elanna Torres, and Captain Kathryn Janeway have been assimilated as Borg drones aboard Tactical Cube 138, but their personalities remain intact thanks to a short-lived anti-assimilation inoculation developed by The Doctor.
The borg collective as a whole didn't join the federation it was just a small splinter group of the borg that joined the federation the main borg collective is still an enemy of the federation and would mostly likely never join the federation instead would keep on trying to assimilate the federation.
In Peter David's 2007 Star Trek: The Next Generation novel, Before Dishonor, which is set after the events of Star Trek: Nemesis, Janeway is assimilated by a rogue faction of the Borg, and becomes their new Borg Queen.
The Borg Homeworld is Earth. That is why the Borg have such a hardon for Earth that they put resources into capturing Earth on the other side of the galaxy and assimilating humanity rather than continuing their geometric expansion out from the Delta Quadrant.
