Verron puzzle box

The puzzle box is a mysterious item given to Sarah Jane Smith by a Verron soothsayer which protects its holder from the power of the Trickster. It protected Maria Jackson and later Alan Jackson during the Trickster's first attempt to destroy Earth by killing Sarah Jane as a child (SJA: Whatever Happened to Sarah Jane?). Later, it alerted Rani Chandra and Clyde Langer to the renewed threat of the Trickster, and protected them and their memories from the switch to a timeline where the Trickster conquered Earth having manifested in 1951. The box continued to protect Clyde and Rani from a Graske working for the Trickster. In exchange for helping them defeat the Trickster, Clyde gave the Graske the box to protect him should the Trickster ever seek revenge. (SJA: The Temptation of Sarah Jane Smith)

It was useless in assisting with the Trickster's plan incite chaos by killing the Tenth Doctor (DW: Turn Left) because the event of Donna Noble meeting the Doctor (DW: The Runaway Bride) occured a little while after Sarah Jane last encountered him anyway (DW: School Reunion).