Green Lantern The New 52 Volume 4: Dark Days by Robert Venditti and Billy Tan
After taking a lot of casualties in the last volume, the Green Lantern Corps is in bad enough shape that the Guardians decide to promote Hal Jordan to head of the Corps. Almost immediately the Orange Lanterns (who are motivated only by greed) attack, hoping to steal whatever stuff is on the Green Lantern home base of Oa. Hal and company (featuring some brand new recruits) just barely beat back the threat when they discover problems with their rings. The energy that powers them is fluctuating badly thanks to a new threat from before the Big Bang--Relic. Relic is a giant, crazy scientist from the universe that existed before the Big Bang. That universe ended when its light-wielders depleted all the light energy they had (causing the Big Bang). Somehow Relic survived and now he is try to stop all the Lantern Corps from using up all this universe's light energy and causing another universal catastrophe. Can Hal Jordan and the Lanterns both defeat Relic and start using their light energy more wisely?
The plot is large and imaginative, possibly bordering on the preposterous. I went with it and found it an enjoyable read. The "history" of Relic is well-written and makes him an interesting opponent that forces Hal not to go it solo. Hal needs to learn leadership skills and this gives him a good opportunity. I was worried the "conserving resources" theme might get too heavy-handed but they don't go overboard with it. They just went overboard with a lot of other elements!