Ray Park
Darth Maul was too good of a villain to be stuck in the prequel trilogy and it’s due in large part to the work of Ray Park. Park has since appeared in Bryan Singer’s X-Men series as well as the G.I. Joe franchise as Snake Eyes.
Jake Lloyd
Young Anakin Skywalker was certainly not as popular as George Lucas had hoped though not due to the fault of child actor Jake Lloyd. Still, Lloyd retired from acting early before going down a rough path — eventually getting arrested after a binge due to mental illness. He’s now in rehab.