Impa is the chieftain of the Sheikah tribe during the Epoch Era. She is one in a long line of Sheikah leaders to be named after the original Impa who assisted Hylia in the Demon War. She is a powerful woman well studied in the arts of stealth, diplomacy, and battle tactics. As King Dromand's guardian Impa is his most trusted subject. Unwaveringly loyal to the Hylian King, she often personally attends to matters deemed important to the crown. A stoic and cool headed leader, her true personality remains hidden from the common man and woman. Impa's most notable act in history remains shrouded in secrecy. She was involved in a plot to take hold of the Timeshift Stone Vault along with King Dromand, which set the Epoch War into motion. What her motivations are and to what extent these dealings have gone on remains unknown.
Timeline of Major Events
Cloaked in black Impa hires Majin Kotage to steal the Hylians own trust key. Unaware of her identity Majin is rewarded money in exchange for his work. Impa then takes the key back to King Dromand in secret.
Impa brings Taden, Tarah, Leif, and Kourtz into the throne room of Hyrule Castle. There they meet with Dromand who gives them a quest. In exchange for freedom and forgiveness of their crimes he asks them to find the one who stole the trust key. Under threat of imprisonment all four agree. Impa then meets them in Hyrule Field and instructs them to find an informant named Haldar, who supposedly has information on Majin.
After learning the trust was stolen by Majin, who had connections with the Zora, Impa falsely tells her agents she believes King Tiburon had ordered the trust's theft. She then instructs them to sneak into Zora's Domain and bring the Zora Trust Key back to her so that it can't be misused by Tiburon.
After taking hold of the Zora and Goron trust keys Kourtz, Leif, Tarah, and Taden are attacked by the Zora forces in Hyrule Field. Impa arrives to help them escape, and orders them to seek refuge in Lon Lon Ranch. Inside Impa receives the Goron and Zora trust keys and takes off. Outside she takes command of a Hylian army that had arrived to trap the Zora.
By chance Impa runs into Majin among the chaos in The Battle of Disharmony. Majin recognizes Impa as his employer, and she reveals that he is indeed correct. She orders her army to capture or kill anyone on the battlefield and then uses a Deku nut to disappear. Later in the night she brings the next two keys back to King Dromand and the two plot on how to get into the timeshift stone vault.
Impa's whereabouts on these days are unknown.
Impa enters the Castle's Dungeon where Leif, Kourtz, Taden, Tarah, Xiaber, and Shinsou have been held since their capture in the Battle of Disharmony. She frees them all and offers them the chance to become Sheikah agents. Everyone but Kourtz accepts. However at that moment living bomb Avarius bursts into the cell. Impa escorts the King and Shinsou to safety while the others stay behind to deal with the bomb. Later in the night survivors of the explosion regroup. Impa officially grants them Sheikah powers. She then orders them to find the three dragons of the land in order to find out the location of the hidden timeshift stone vault.