Completing Reciprocal Rune encounters have a chance to drop Stolen Runes. Admittedly, though, your best bet to get them is to buy them from Eris.
A Zaouli's Bane with Firefly would be preferable. The Exotic one though is a little bit of a disappointment (but opinions differ based on Guardian to Guardian).
Destiny is based on a random number generator (RNG). You might have to beat Crota's End on Hard a few times to get the Graverobber sparrow. (NOTE: loot on completing Crota's End will drop only once per week, depending on the difficulty.)
Hate to say this, but Thorn... is kinda a waste of time. It works, yes. It can cause lingering damage over time, I give it that, but it's been nerfed to death now, which makes it quite weak now.
Hard Light is one of the BEST auto rifles in Destiny. The exotic perk on it is extremely helpful for PvE and PvP.
Gjallarhorn and Raze-Lighter are excellent choices for Wrath of the Machine.
...we've already gotten them?
They claimed they added a "connection referee" for this stuff...
The old LDR 5001, Y-09 Longbow Synthesis and 1000-Yard Stare are pretty good but a little too overused. The Exotic Black Spindle and Event Horizon from the Crucible aren't too bad either.
I'm pretty sure the theme used when fighting the walkers is the Rise of Iron main theme. And Ad Victoriam is the piece played when the Gally is being forged.
No worries! You still can get the normal Gjallarhorn from a questline. Just finish the normal Rise of Iron questline and Echoes of the Past to start it.
Parts are in alternate versions of Dock 13, The Blast and the Refinery, which you access from the Plaguelands.
I think it's possible?
Eyasluna is earned through Classic Playlists; look for one with Luck in the Chamber.
You can access certain areas of the Plaguelands with these; so far, Site 6, Bunker Triglav and the Refinery have areas where keys are required.
For me, I'd say Hawkmoon for PvP, but you'll probably have different opinions; Thorn has been nerfed to death so it is no longer the king of the hand cannon hill, The Last Words is good but too overused. Red Death is good in PvE because every kill starts health regeneration, especially in Crota's End where health regeneration is NEEDED.
It depends on your playstyle. Hunters specialize in agility while Warlocks specialize in abilities; personally, I main a Hunter, but Warlocks work well for me as well.
Kinda late there, mate. Bungie has completely removed the bounties; but to unlock them, the questline "The Mountaintop" had to be completed.
Hate to tell you the hard truth, but the Gjallarhorn has been nerfed ever since its introduction; the Gjallarhorn was introduced in Year 1, and was immensely powerful that they left it out of Year 2; those who used it then didn't find it as powerful as before though some may beg to differ. The Y3 Gjallarhorn has been immensely nerfed compared to the Gjallarhorn when originally introduced. This actually made it one of the truly Exotic weapons in Years 1 and 2.