On the subject of hidden exotic weapon perks (Destiny)
Fairly recently I came across a thread on reddit mentioning 'hidden exotic weapon perks'. I had suspected for a while that Gjallarhorn was detonating based on proximity even though the perk didn't exist on the weapon tree, and this thread inspired me to go out and start testing these hidden perks to see if they were rumors or actually true.
While I'm glad the ones I've tested thus far have come back positive, I'm still really intrigued about the nature of these 'hidden perks' in general, as the list of exotic weapons and their corresponding perks is still mostly incomplete. Do ALL exotics have hidden perks? or only a select few?

That hard light bubble could use some exploration.
Fairly recently I came across a thread on reddit mentioning 'hidden exotic weapon perks'. I had suspected for a while that Gjallarhorn was detonating based on proximity even though the perk didn't exist on the weapon tree, and this thread inspired me to go out and start testing these hidden perks to see if they were rumors or actually true.
While I'm glad the ones I've tested thus far have come back positive, I'm still really intrigued about the nature of these 'hidden perks' in general, as the list of exotic weapons and their corresponding perks is still mostly incomplete. Do ALL exotics have hidden perks? or only a select few?
Look at Hard Light and the shoot through bubble perk next! I still haven't actually witnessed that perk in action.

That hard light bubble could use some exploration.
I can confirm that Jellyhorn does INDEED have proximity detonation, as I have blown myself to smithereens multiple times, trying to shoot by a thrall that is next to me to hit say, a wizard in the distance.
I do not consider it a perk -_-
And as for Hard light, I've been on the receiving end as a Titan Defender one time. It was....a sad moment.

Hidden perks I know of...
Cool video! Keep it up; I really enjoy your analysis.
Here are more hidden perks I'm aware of:
Truth holds 3 rockets. Display bug? Maybe, or maybe the hidden perk is "Tripod!"
MIDA staggers targets far more often than it should based on it's stats. That would be the "High Impact Rounds" perk, right?
Man... I can't remember any others right now, but I swear I know of more.

Hidden perks I know of...
MIDA didn't ever stagger targets until after it was buffed with all the other scout rifles.
I distinctly remember taking it out after the patch and noticing the change. So, I'm not sure if should be considered a hidden perk, because it would have had that before it was buffed...but it didn't.
Not that I'm complaining it has it now or anything- it's quite useful for knights and captains.

Truth
Truth holds 3 rockets. Display bug? Maybe, or maybe the hidden perk is "Tripod!"
The third rocket in Truth's mag was explicitly added a while back. It took a patch or two before the UI caught up, but it's definitely supposed to hold 3 rounds. Not hidden.

Thunderlord
Nice vid! For Thunderlord, I think that it's every third precision shot triggers the Firefly-like effect, but the counter resets if you miss shots. Not 100% on that, but it seemed to hold up in the cursory testing I did a while back. A great place to try this is the Hive Door at the end of The Dark Beyond.

Sounds right?
I remember it proc'ing significantly more often with head shots. If you aren't using it against a boss/bullet sponge, perfect balance is really the perk to go with for this very reason.

Hidden perks I know of...
The knockback (stagger) effect was actually explicitly added to MIDA as part of the big exotics patch in December.
MIDA Multi-Tool
MIDA rounds now have increased knockback against targets in both PvE and PvP

Hidden perks I know of...
The knockback (stagger) effect was actually explicitly added to MIDA as part of the big exotics patch in December.
MIDA Multi-Tool
MIDA rounds now have increased knockback against targets in both PvE and PvP
Right, so it wasn't hidden then. I knew I didn't imagine that.

Hidden perks I know of...
Right, so it wasn't hidden then. I knew I didn't imagine that.
Depends what you mean by hidden, I guess. It's not a secret in that Bungie has said the gun behaves that way on purpose. But it's also not shown on the item card at all, so it's hidden to anyone who isn't up to speed on patch notes.

Thunderlord is a headshot machine, regardless of perk
For me, if I aim for center mass with Thunderlord, and I do *not* have Perfect Balance turned on, then every other shot hits the head. The kick is literally perfect in that way. With Perfect Balance, I can hit the head a couple of times in a row, but I find that the kick being so small actually means I often lose sight of my target (since only their head is above my barrel), whereas with field scout on, I can easily track my targets and still get loads of headshots.
I have gotten 4 machine lord medals in one clip with Thunderlord before. 12 kills in one mag, thanks to Field Scout.
Now, for the purposes of proccing lots of explosions, you'd want perfect balance, but for pure killing power, I vote field scout.

Ditto
Agreed. It can be an unwanted perk.

Thunderlord is a headshot machine, regardless of perk
For me, if I aim for center mass with Thunderlord, and I do *not* have Perfect Balance turned on, then every other shot hits the head. The kick is literally perfect in that way. With Perfect Balance, I can hit the head a couple of times in a row, but I find that the kick being so small actually means I often lose sight of my target (since only their head is above my barrel), whereas with field scout on, I can easily track my targets and still get loads of headshots.
I have gotten 4 machine lord medals in one clip with Thunderlord before. 12 kills in one mag, thanks to Field Scout.
Now, for the purposes of proccing lots of explosions, you'd want perfect balance, but for pure killing power, I vote field scout.
Yeah, for PvP I think it comes down to personal preference. Although I generally find the perfect balance recoil to fit pretty well with how I use it, it's definitely not for everyone.
On the subject of hidden exotic weapon perks
Cool video! You've earned yourself a sub! ;P
I didn't actually know about these hidden perks. I'll have to look out for more.

On the subject of hidden exotic weapon perks
Pretty cool. I'd heard about Thorn, but not the others. I always figured the Thorn thing was a bug that they decided not to fix - I could see it not being a high priority bug since it's going to behave that way once it's upgraded anyway. Gjallarhorn, Plan C, and Thunderlord, though, seem more like things that must have been added intentionally.

Thunderlord is a headshot machine, regardless of perk
I just got this gun this weekend, excited to get it leveled up based on what y'all are saying

Thunderlord is a headshot machine, regardless of perk
Thunderlord is one of my favourite guns in the game. I personally run it with field scout though. We should Crucible it up sometime and let all the plebs hear the sound of our rolling thunder!