So since the launch of Destiny, I've run The Undying Mind strike 220 times. A huge portion of those runs were for the revered Imago Loop, the strike exclusive weapon, and up until RoI, the only legendary light relevant Hand Cannon that could roll with Fatebringer's Perks. Funnily enough, I've actually been recording all my drops for this strike since Rise of Iron's launch. 61 runs, to be exact.
(Note: I only listed what I could be considered to be the best perk in the middle column)
1.Imago Loop: Reactive Reload, Rifled Barrel, Spray & Play
2.Mark of the Undying Mind
3.Mark of the Undying Mind
4.Imago Loop: Last Resort, Reinforced Barrel, Army of One
5.Mark of the Undying Mind
6.Imago Loop: Reactive Reload, Hand Loaded, Spray & Play
7.Imago Loop: Exhumed, Reinforced Barrel, Icarus
8.Imago Loop: Last Resort, Casket Mag, Luck In The Chamber
9.Mark of the Undying Mind
10.Imago Loop: Rangefinder, Hand Loaded, Icarus
11.Mark of the Undying Mind
12.Mark of the Undying Mind
13.Mark of the Undying Mind
14.Imago Loop: Surrounded, Rifled Barrel, Life Support
15.Imago Loop: Partial Refund, Smallbore, Grenadier
16.Mark of the Undying Mind
17.Imago Loop: Spray & Play, Reinforced Barrel, Grenadier
18.Mark of the Undying Mind
19.Imago Loop: Last Resort, Hammer Forged, Reactive Reload
20.Imago Loop: Danger Close, Feather Mag, Grenadier
21.Imago Loop: Surrounded, Snapshot, Luck In The Chamber
22.Mark of the Undying Mind
23.Imago Loop: Rescue Mag, Hammer Forged, Grenadier
24.Mark of the Undying Mind
25.Mark of the Undying Mind
26.Imago Loop: Underdog, Smallbore, Life Support
27.Mark of the Undying Mind
28.Mark of the Undying Mind
29.Mark of the Undying Mind
30.Mark of the Undying Mind
31.Imago Loop: Outlaw, Extended Mag, Firefly
32.Mark of the Undying Mind
33.Mark of the Undying Mind
34.Mark of the Undying Mind
35.Imago Loop: Outlaw, Reinforced Barrel, Army of One
36.Imago Loop: Danger Close, Extended Mag, Life Support
37.Mark of the Undying Mind
38.Mark of the Undying Mind
39.Mark of the Undying Mind
40.Imago Loop: Danger Close, Reinforced Barrel, Life Support
41.Mark of the Undying Mind
42.Imago Loop: Surrounded, Snapshot, Firefly
43.Imago Loop: Rescue Mag, Rifled Barrel, Mulligan
44.Mark of the Undying Mind
45.Imago Loop: Exhumed, Snapshot, Reactive Reload
46.Imago Loop: Hot Swap, Casket Mag, Hidden Hand
47.Imago Loop: Underdog, Hammer Forged, Firefly
48.Mark of the Undying Mind
49.Mark of the Undying Mind
50.Mark of the Undying Mind
51.Mark of the Undying Mind
52.Mark of the Undying Mind
53.Mark of the Undying Mind
54.Imago Loop: Life Support, Rifled Barrel, Reactive Reload
55.Imago Loop: Partial Refund, Hand Loaded, Firefly
56.Imago Loop: Triple Tap, Hammer Forged, Army of One
57.Imago Loop: Relentless Tracker, HCR, Icarus
58.Mark of the Undying Mind
59.Imago Loop: Rangefinder, Smallbore, Mulligan
60.Mark of the Undying Mind
61.Imago Loop: Underdog, Casket Mag, Army of One
If you were (are) looking for the pseudo Fatebringer, then I would have stopped at #31.
You pretty much had it with that one.
IMHO - running Fatebringer with field scout over explosive rounds was a much better setup.