ToME: the Tales of Maj'Eyal

As you can see, no number is near my positive energy bar, and none of my equipment says that it stops energy decay. My Ghoul Palladin feels lucky about it.

It's the Summertide Phial. It gives 0.20 positive energy/turn, thus preventing decay.

But only when equipped by a sun pally, meaning it wouldn't have been there before you wore it.