Artwork by Doug Mahnke, Keith Champagne, Christian Alamy and Mark Irwin
Ever since the Geoff Johns and Co. introduced the extended spectrum of emotional colors into the DC pantheon, the Indigo Tribe is given the least amount of panel space. At first, this seemed like an storytelling decision, one made simply because there were too many characters interacting at the same time, and the Indigo's were mysterious enough to be kept vague. After a while, I assumed the lack of content featuring the Indigo Tribe was an editorial decision, one that came from polls and marketing numbers that showed readers preferred the Red Lanterns or Agent Orange to the enigmatic tribe that doesn't use English on a regular basis.
Now, it's pretty obvious Johns has had plans for the Indigo Tribe for quite some time. The last time we really saw the Indigo Tribe was way back during the "Blackest Night" event when Indigo One kidnapped Black Hand from under everyone's noses before presenting him as the newest tribe member. It was a haunting scene, one that threw into question everything readers had thus far assumed about the Indigos. Sometimes, not knowing the threat is worse than knowing just how bad it is, and Johns is definitely playing that card with this plot.
Basically, Sinestro read the Book of Black and saw the end of the Green Lantern Corps - an idea that's been seeded throughout Green Lantern since the relaunch - and now he needs Hal's help to stop it from happening. In true Green Lantern style, the Indigo Tribe shows up to corral Sinestro for themselves. Over on Oa, the Guardians are getting pretty hardcore, talking about murdering a Corpsman. It's a little uncomfortable, but I'm sure that's exactly what Johns wants.