Les recently upgraded his flash-pumped laser project by swapping a standard Nd:YAG rod for a yellow Nd:Ce:YAG version. His initial setup produced 72.8 mJ pulses, but the new rod pushed output to 153 mJ, more than doubling the performance. This efficiency jump is due to cerium doping, which absorbs energy from the flashbulb that would otherwise be wasted. The cerium atom acts as a fluorescent donor, transferring that energy to the neodymium atoms that perform the lasing action. Beyond just raw power, the new rod offers better longevity. The cerium acts as a protective shield against the degradation caused by UV light from the flashbulbs, which often breaks down the coatings on standard laser rods over time. Les, known for his previous work on tattoo removal devices and custom laser drivers, views this swap as a simple and effective upgrade for his hardware. This experimental setup demonstrates how specific crystal doping can significantly improve laser performance in DIY applications. While the current setup is a custom build, the potential for using different crystals opens up options for hobbyists who build their own high-pulse lasers. Les remains a regular figure in laser-based hardware modification, and his latest result highlights the tangible gains that come from understanding the material properties of the components in a laser cavity.