The 415th was involved in the First Battle of Geonosis in a limited way, losing their first Jedi General there. History The Clone Wars The Beginning of the War
The 415th has mental shielding due to leftover Ragnos defences. They had some training in Prakith Sword Combat, Prakith Hand-to-hand, Archery and Medieval Siege Weapons from their time in the Time loop there. The 157th Battalion, then led by Major Jaws when it was a company, was even more suited for non-standard ops, even having a different colour scheme to the normal golden one. Used for exploratory and as auxiliary forces, it mainly consisted of standard troopers, although its ranks included various specialists such as Advanced Recon Commandos and a full time Clone Commando Squad 'Zeta'.
The 415th Exploratory Corps was a military division of clone troopers.