Currently on my titan. Also have bitter steel and hanged man. Fermi solution also. Been playing since beta and my titan is in the high 50's with DO. I got it around level 48. Got the other 2 on my hunter which i dont think is even a 20 yet. I hate to say it but just keep farming bounties and nightfalls. Nightfall for the 500 xp and then the boost for bounties.