Geeka was a goblin and assistant or guard to the Great Shaman. When they caught Jak Ohmsford and his party, Geeka insisted to deliver them to the Shifter who asked for them, not directly to Brona.
As every Goblin, Geeka was ambitious and treacherous. When Ohmsford tied the Shaman, Geeka saw this and found the opportunity to kill him. Geeka told Jak that he has the key to the Deep Well where his friends were kept prisoners in exchange for the Magic Torc. Jak further persuaded Geeka to follow him by mentioning him the Helm of Command. Geeka assisted Jak to find their belongins and lower them to the Deep Well as the goblin guards noticed them.
When they reached the Valley of Shale, Allanon told Jak to give Geeka the Torc. With this, Geeka combined its magic powers with others's to reforge the Sword of Shannara. He followed the party to the Hall of Kings. When they were trapped, Jak and Brendel helped Geeka go out and find a way to free them, however he was lured by the Helm of Command. But as with everything else there, it was trapped; a ray burned Geeka, while it fell on the floor, opening a trapdoor.