The Staff of One was originally wielded by Tina Minoru, mother to Nico and was immensely powerful as the dreaded Dormammu trembled at the sight of it, knowing its power. It was passed onto Nico when Tina tried to stab her with the staff, but Nico's body managed to absorb it without ill effects.
The Staff of One is used by simply stating a word or phrase, and a spell that relates to that word or phase will occur (e.g. saying "Smoke" would cause the Staff of One to release smoke, or "Caffeine Injection" charges the target with additional energy). The major limitation of the Staff of One is the fact that each spell can only be used once; if any spell is attempted again the staff will instead have a completely random effect.
To release the Staff of One Nico must bleed and instinctively repeats the phrase, "When blood is shed, let the Staff of One emerge!". It also passes through the middle of her sternum, appearing through whatever clothing she is wearing at the time and piercing anything directly in front of Nico. Anyone can use the Staff of One, even without training or magical affinity, which is partially explained as everyone having magic but most people needing tools to bring it out.
On the Runaway's trip to New York City, in the year 1907, Nico got caught breaking into a bank that supposedly had a means to get back home. An ancestral version of the Punisher knocked her out and when Nico awoke, she was in a dungeon. Nico's ancestor the Witchbreaker was carrying another magical staff called the Witchbreaker's staff. The Witchbreaker, in actuality Nico's great-grandmother, tortured Nico to see if she had the strength to be a powerful sorceress. After a while the Witchbreaker deemed her worthy. Nico withstood unimaginable pain and this enabled her to gain far greater magics and transformed the appearance of the Staff of One. The staff's new form is not only much more powerful than the original Staff of One, it also increased Nico's ability to use magic without the staff.
Users outside the Minorus
List Of Spells Used
Freeze: Causes Stacey Yorkes to become immobilized
Freeze: The second time causes pelicans to fly out of the staff
Smoke: Smoke comes out of the staff to help the Runaways escape
Away: Nico teleports away from Alex Wilder
Mud: Mud shoots out of the staff and hits Karolina Dean
Burst: Causes a group of graffiti artists' spray paint cans to explode
Rock and Roll: Makes an earthquake that caves in the hostel
Waterproof: Makes a waterproof bubble that the Runaways travel in to get to the Pride
Float On: Nico makes the Stein's float in the air
Dance: Alex uses the staff to unfreeze Nico
Bondage: Alex uses the staff again to shackle Karolina's parents (off panel)
Bondage: Alex unlocks the secret of using the same spell twice and uses the spell to shackle Karolina
Hands Off: Nico destroys Alex's Fistigons
Free your minds: An evil witch (Marie LeVeau) casts a spell that turns some of Nico's new friends against her. This spell cancels this spell.
Wardrobe Malfunction: Changes Marie back from wolf to human
Deflector Shields: Causes Marie's magical attack to bounce off of Nico
Deconstruct: Nico uses this spell to take apart one of the Wrecking Crew
Flashback: Makes Nico see the last few moments of a future version of Gert's life.
Rockstars: Flaming rocks fly out of Nico's staff. But they hit Old Lace instead of Victor Mancha.
You Suck: Causes Turbo's wrist turbines to spin in reverse, sucking air in and causing them to malfunction
Insulation: Temporarily takes away Victor Mancha's powers
Shine on You Crazy Diamond: Encases Ultron in a diamond
Fumigation: Nico uses this in a battle with Tarantula (off panel)
Fumigation: Nico forgets she already used this spell and it teleports her and Karolina to the outskirts of Los Angeles.
Acid Rain: Makes a cloud of Acid rain that dissolve the security daemons
Old Lace to Old Yeller: Changes Old Lace into a dog
Hellfire: Shoots fire balls at Spider Man
Dreamtime: Puts Spider-Man to sleep
Sunburst: Shoots a beam of light at a Cloak impostor
Detox: Chase Stein uses this to flush the MGH out of the Cloak impostor's system
Get to Work: Transforms Chase's "List of things to do when I'm 18" into a wrench
Revelations: When a past version of Geoffrey Wilder disguises himself as Alex, Nico uses this to change him to his true form.
Shut Up: Knocks Chase out of the way with spiraling energy
Pixies Find the Leak: Nico conjures up Pixies to find out how the Pride have been spying on them.
Forget: Erases Geoffrey Wilder's memories of what happened
Caffeine Injection: Gives Molly Hayes a boost of energy
Now here comes the sweet talk: Gives Xavin the voice of a monster's wife to soothe him.
Get Lost: Disorients Kate Bishop
Chill Out: Freezes all of the Runaways and Young Avengers, making them extremely cold
Wake Up: Wakes everyone up when they were knocked unconscious by Noh-Varr
Prodigum Effodio (Excavating Monster in Latin): Creates a monster created out of a shield that gets the team into the Cube
Be Quiet: Chase uses this spell to silence Nico, making her talk in a whisper
Pretty soon, I'll just be a bad dream: Knocks Nico unconscious
Going Down: Phases the Runaways through the roof to escape the Punisher
Crash: Puts the Kingpin's ninjas to sleep
Open Sesame: Makes bank employees open their vaults