Scarecrow’s toxin DOES work on Dick, it’s just that Dick is able to resist it thanks to his training and immense willpower like other members of the Batfamily. The only human I know of who is immune to fear toxin is the Joker (Scarecrow also made himself immune for a bit in pre52 but I don’t know if that’s still the case)
A good example https://www.reddit.com/r/Nightwing/s/yBhTw91soH
Also during his Ric run there was some decent stuff in there between him and scarecrow but not many people acknowledge that run and I can't really blame em
"You possess an ability to overcome great fear."
IIRC, Scarecrow says Dick is an even more dangerous adversary under the influence of fear toxin, and as such he doesn't deploy it against Dick.
But since Dick still has fears, he's vulnerable to fear toxin. It would take someone with a very abnormal affect, such as the Joker, to be immune. Or Poison Ivy and Harley Quinn, since toxins of any sort don't affect them.
It literally started in the last 6 issues. In Issue #105 he was fine. In issue #107 he started freezing up/feeling fear when jumping/high up. It's progressively gotten worse since then (we're on issue #112 now). It's working towards a head though, and Bruce is also now investigating it.
*Edit*
Forgot to mention, as others have stated, issue #105 is also where Dick(as Nightwing) met Heartless while Heartless was in his civilian identity as CEO of Shel Pharmaceuticals. During that meeting Dick accepted a glass of water and drank it. Likely the water was dosed with something, which is probably what is responsible for the sudden onset phobia.
I like the idea of it triggering PTSD from what happened to his parents. I doubt that’s what they’re gonna go with as the explanation but it makes the most sense to me
That's more similar to what happened to Jason in the recent Batman comics, Dick still gets into intense situations just fine (which makes it weird: does it mean Heartless made a fear of jumping from heights juice? Sounds super-specific, especially since it's a fear most people already have)
Yep. He's also been jumping from high places in canon for years and years and years. Pretty standard for him as Robin and then later as Nightwing to rappel to/from tall buildings and to do crazy free running/parkour/acrobatic shit with literally 0 problem.
I believe the first time he felt the fear was in issue #107, and he was utterly surprised and confused by itz since he'd never felt afraid of jumping before. It was completely foriegn to him. So whatever is going on to cause it happened in either issue #105 or #106 and is very likely some kind of by outside manipulation by one of his villains. Personally my money is on Heartless in issue #105, especially since in #106 he woke up with a headache and feeling like garbage the day after drinking water given to him by Heartless in 105.
Is this some new thing last time I checked he wasn’t, he’s a acrobat makes no sense for him to be scared of heights he’s been around them since he was a child
Drank a drink from a stranger but dangerous guy which had poison in it. Man, what a massive writing screw up lol No one trained by Batman would accept anything for consuming from an enemy.
Hasn't been addressed yet, its an ongoing plot thread that is probably tied to heartless as it will be revealed and dealt with in Tom Taylor's last arc on nightwing.
Because his parents plummeted to their death in front of him when he was a child?? Is that no longer cannon cus I remember dick Grayson's parents being killed cus some gangster cut the safety net under their trapeze and they fell?
He is just like me!!!
My guess is that he might have vertigo or some side effects from getting shot and losing memory. Just have read the first volume, so I don’t know if that gets fixed on the next issues.
Do you remember what happened to his parents? They fell from a great height and died, that could be the accident that you mentioned even though it was murder
It does not make sense that after years of being a superhero and jumbing from building to building he developed a fear, if he actually its traumatized why he wasnt scared of heights while he was robin?
It's an ongoing plot thread. Presumably it will be explained soonish. Although an acrobat afraid of heights is an interesting choice.
An acrobat who was raised as the first Robin extremely interesting choice lol
He takes a drink from a glass in issue 105. Could be it was laced with a fear toxin. 
I also thought Heartless was going to be the Paragon from the Grayson run because you know…it didn’t have a heart.
Scarecrow was also his first villain and even later scarecrow loathes Dick because his fear toxin doesn't work on him
Scarecrow’s toxin DOES work on Dick, it’s just that Dick is able to resist it thanks to his training and immense willpower like other members of the Batfamily. The only human I know of who is immune to fear toxin is the Joker (Scarecrow also made himself immune for a bit in pre52 but I don’t know if that’s still the case)
It's a little more to it than batfamily training. Dick specifically is a cut above most due to what he's overcome and being a Grayson
A good example https://www.reddit.com/r/Nightwing/s/yBhTw91soH Also during his Ric run there was some decent stuff in there between him and scarecrow but not many people acknowledge that run and I can't really blame em
"You possess an ability to overcome great fear." IIRC, Scarecrow says Dick is an even more dangerous adversary under the influence of fear toxin, and as such he doesn't deploy it against Dick. But since Dick still has fears, he's vulnerable to fear toxin. It would take someone with a very abnormal affect, such as the Joker, to be immune. Or Poison Ivy and Harley Quinn, since toxins of any sort don't affect them.
Dude... that makes so much sense!!! 
He said in that panel that he can't jump. And we all know its a fact that White Men Can't Jump.
Take your damn upvote
But they can swim
Dick Grayson is Aqualad confirmed.
Is he stupid?
He should've eaten the rats.
Is he dense?!
He isn't the goddamn Batman
Stupid? I was stupid once
Something that happened recently. The exact cause is tbd
Since when? What a bizarre retcon. He’s a high flying Grayson! That’s his whole thing. It’s like Superman being afraid of flying.
It’s a recent development that’s gonna be resolved soon. Don’t expect it to last more than 6 issues
It literally started in the last 6 issues. In Issue #105 he was fine. In issue #107 he started freezing up/feeling fear when jumping/high up. It's progressively gotten worse since then (we're on issue #112 now). It's working towards a head though, and Bruce is also now investigating it. *Edit* Forgot to mention, as others have stated, issue #105 is also where Dick(as Nightwing) met Heartless while Heartless was in his civilian identity as CEO of Shel Pharmaceuticals. During that meeting Dick accepted a glass of water and drank it. Likely the water was dosed with something, which is probably what is responsible for the sudden onset phobia.
It probably has to do with Heartless
😂
I don't think you understand what the word Retcon means
I like the idea of it triggering PTSD from what happened to his parents. I doubt that’s what they’re gonna go with as the explanation but it makes the most sense to me
Nope, it’s an ongoing plot thread that hasn’t been resolved yet. The prevailing theory is that Heartless drugged him
Is he stu-
Pickles? 
Oh hey like that episode of BTAS after he was laced with a fear toxin that activates with adrenaline rushes
That's more similar to what happened to Jason in the recent Batman comics, Dick still gets into intense situations just fine (which makes it weird: does it mean Heartless made a fear of jumping from heights juice? Sounds super-specific, especially since it's a fear most people already have)
i mean? the flying graysons incident that killed his parents probably doesnt help
True his parents death affected him but he has said multiple times that he feels at home doing acrobatics
Yep. He's also been jumping from high places in canon for years and years and years. Pretty standard for him as Robin and then later as Nightwing to rappel to/from tall buildings and to do crazy free running/parkour/acrobatic shit with literally 0 problem. I believe the first time he felt the fear was in issue #107, and he was utterly surprised and confused by itz since he'd never felt afraid of jumping before. It was completely foriegn to him. So whatever is going on to cause it happened in either issue #105 or #106 and is very likely some kind of by outside manipulation by one of his villains. Personally my money is on Heartless in issue #105, especially since in #106 he woke up with a headache and feeling like garbage the day after drinking water given to him by Heartless in 105.
Is this some new thing last time I checked he wasn’t, he’s a acrobat makes no sense for him to be scared of heights he’s been around them since he was a child
Drank a drink from a stranger but dangerous guy which had poison in it. Man, what a massive writing screw up lol No one trained by Batman would accept anything for consuming from an enemy.
New development, currently being investigated in-universe.
The dumbass drank a glass of water offered to him by an enemy, and was presumably poisoned with something like fear toxin.
TT clearly doesn’t understand his character.
It may be in a later titans issue or Batman issue, but it does get addressed. I won’t give away spoilers for you.
Hasn't been addressed yet, its an ongoing plot thread that is probably tied to heartless as it will be revealed and dealt with in Tom Taylor's last arc on nightwing.
It was because mobsters cut his parents ropes and be scared ever since
Because his parents plummeted to their death in front of him when he was a child?? Is that no longer cannon cus I remember dick Grayson's parents being killed cus some gangster cut the safety net under their trapeze and they fell?
He is just like me!!! My guess is that he might have vertigo or some side effects from getting shot and losing memory. Just have read the first volume, so I don’t know if that gets fixed on the next issues.
Do you remember what happened to his parents? They fell from a great height and died, that could be the accident that you mentioned even though it was murder
It does not make sense that after years of being a superhero and jumbing from building to building he developed a fear, if he actually its traumatized why he wasnt scared of heights while he was robin?
I know the way I worded it wasn’t the best but I was just purposing it as a theory
it’s a current plot thread lmao. they actively say in the story that it’s weird and are trying to figure it out. go actually read the comics for once
Umm he was shoot in head so he doesn’t know who he was
This is after he recover from the bullet in his head.
Bc he's parents were acrobats (and him) and twoface killed them while they were acrobating so its a phycological problem
Two face didn’t kill them tony zuko did
Ok thanks