Knuckles is the secondary antagonist of the Danger Rangers episode "Safe and Sound." He is the warthog bodyguard of Decibulls' band manager Buck Huckster who never allows non-performers in the studio, not even fans.
When Knuckles catches Ranger Sully (the Decibulls' #1 fan) discovering the source of the ear-damaging volume, Knuckles locks him in a loud speaker.
Eventually, Knuckles and Buck are arrested for their crimes.
Knuckles is voiced by Kevin Michael Richardson who also voiced Ranger Burble throughout the series.