Energy issues?

[Nightcrawler92]

What are the issues that Superman was in his altered state during the 90s? Is there a list somewhere?

[Kuwagaton]

Yeah, it starts in Adventures of Superman #545 and ends in Superman Forever, Triangles 1997/15 to 1998/21. Although the wheels that set the story in motion were rolling some time before it actually starts, you basically get everything you need through the story itself. Check out the Superman Blue trade just recently released. And maybe the Superman Wedding story for a little more context.

This is a guide on how the Triangle reading system worked:
http://comicsalliance.com/ask-chris-...angle-numbers/

Here's a detailed breakdown on the whole saga:
http://comicsalliance.com/electric-b...ric-blue-year/

And finally... what you asked for, a reading list:
http://www.comicsbackissues.com/comi...r-post-crisis/