WARNING: The following article contains spoilers for Injustice 2 #64 by Tom Taylor, Bruno Redondo, Juan Albarran, Gabe Eltaeb and Wes Abbott, on sale now.
In the Injustice universe, Sinestro has been depicted in similar fashion to his mainstream DC counterpart. The arrogant soldier fell from grace after wanting to exploit the power of fear, leaving behind the Green Lanterns to form the Yellow Lanterns. However, he took his lust for cosmic order to the extreme, siding with Superman's militant faction to rule Earth, proactively planning to spread the Kryptonian's might across the galaxy.
When the regime fell, Sinestro was imprisoned on Oa for his war crimes, seemingly waiting for another chance to strike at the Guardians. But as the Injustice 2 arc has played out, he's actually ended up a Green Lantern once again, along with the repentant Hal Jordan, as they look erase their sins and save Oa, the Guardians and the Corps from the wrath of Atrocitus and the Red Lanterns.
Alas, it's a redemption that, while sweet, ends up being short-lived. In Issue #64, Sinestro meets his death... at the hands of his own daughter, Soranik Natu.
After saving Hal from certain demise, Sinestro moves in to rescue Soranik, who's under the mind-control of Starro's spores, basically making her a disciple of his master, Atrocitus. He intercepts her just as she's about to kill the new Teen Titans (allies of the Green Lanterns), but in swift retribution, she puts a blade through him. It's a mortal blow but he achieves his objective, pulling the spore off so he can lay eyes on her one last time.
In a rare tender moment, we see how vulnerable the villain-turned-back-hero is as he confesses his love for her, and wishes he were a better example. He also reveals the truth about her mother's passing before succumbing to his injuries, leaving the Corps a key member short just as Brainiac arrives to destroy everyone, heroes and villains alike.
It's a bittersweet ending, as Sinestro did cause a lot of havoc in this universe. Not only did he inflict pain on millions by aligning with Superman, he stabbed John Stewart to death, ironically in similar fashion to how he himself died. Sinestro killed Kyle Rayner as well, and corrupted Hal into joining the Yellow Lanterns under Superman's rule. To top it off, he coaxed Hal into killing Guy Gardner, which is why Guy's ghost is haunting Hal as a form of PTSD and why both men were held prisoners of the Corps.
But the fact he put ego aside and genuinely came to the Green Lanterns' aid in their time of need, especially to help the Guardians who condemned him says a lot. Sure, it was all due to him wanting to save his daughter -- whether she liked him or not -- but in the process, he made sure he protected Hal, or as he called him, "my best student."
Along with tremendous willpower, Sinestro showed he still had faith in the universe. Despite Starro breaching Oa's Central Power Battery, he never gave up in the face of adversity. And in this final stand he made up for the lives he claimed by saving countless heroes in the field here, so much so he even left Hal in amazement. The ex-Leaguer clearly recognized his former mentor could be as heroic and selfless as he wanted, and in so doing, Sinestro leaves behind a legacy of inspiration for everyone.
His turn to the light may have been a bit late, but the timing couldn't have been more perfect: Hal needed motivation, as did the rest of the Corps. Soranik finally got some sort of closure and saw her dad die a war hero, and the Guardians grew to realize no matter what, hope is never truly lost. Now, let's pray they can all use these tools and harness the strength which remains because Brainiac's army -- repurposed versions of the Manhunters (the Guardians failed space police experiment) -- are bearing down and doing so without mercy.