Lock him in a pit with a removable barrier between him and a massive horde of boomer knights. Give him a white engram painted yellow, telling him its an exotic engram and he can use whatever's inside to fight off the knights. When he finds a white weapon, he'll beg for something better, hoping to evade his inevitable death. That's when you agree to give him a real exotic engram. However, you don't tell him that it contains a non upgraded no land beyond. Once he finds this, and begins begging for another chance at decrypting something decent, tell him he's out of chances. Every knight he manages to kill drops a legendary engram containing no land beyond or a legendary for another class. Backed up in a corner, begging for mercy, he'll look at you, tears in his disgusting yellow eyes, and plead that you let him live. This is when you deliver the nail in the coffin. You jump in, destroying all the knights with your mystical gurglehorn. Standing over Rahool, he begins to thank you, but you force palm/knife/punch him in his pathetic blue face. After beating him to near death, you leave him in the pit, watching him try to stand up and laughing at him. You then gather up all the guardians in the tower to watch his death. You hand him one final exotic engram, containing no land beyond of course, and maniacally laugh at Rahool, hoping to somehow escape his fate. Green engrams are distributed among all of the guardians watching. Walking away, you yell to master Rahool. "It was always blue!" You finally give the command for all of the guardians to begin pelting him to death with his horrible green engrams. [spoiler]or you could just stab him with a rusty spoon[/spoiler]