A few weeks back, I mentioned that
Green Lantern 58 (Jan. 1968), was a pretty punchtastic issue. In "Peril of the Powerless Green Lantern!" written by Gardner Fox and inked by Sid Greene, GL finds he is having strange reactions to his adventures, such as overwhelming fear, greed, and sadistic tendencies toward criminals. For example, he really lays into three common thugs:

The Guardians diagnose him with combat fatigue and strip him of his ring, but he still has to face some challenges, as detailed in
this earlier post.
Also in this issue, a powerless Hal Jordan spends two pages beating the shit out of a bear:

I can tell you right now, that bear does not appreciate the taste of Florsheim.