The "deer call" scene. The call does a spot-on imitation of Bambi's mother (and it's a creepy, gentle repetition of "I'm here...It's me...Hello...") which combined with Bambi's last shred of hope of seeing his mother alive again, almost gets him mauled by a pack of hunting dogs and shot. He's literally paralyzed with fear when he sees the hunting dogs on his way.
Just the whole situation up until the dogs is damn creepy. Alone in a deserted forest, a disembodied voice calling out to you, luring you out onto an empty field that is completely white and with nowhere to hide. And still that voice keeps calling. Bambi himself was pretty freaked out once he saw the meadow. He knew something was wrong but he just didn't want to give up hope.
A reminder this was based off of a scene in the original book, but with the parental fear intensified. The Great Prince catches up with Bambi, just in time to see a faint glimpse of the hunter's scope, and the sight of his son about to mauled by a pack of vicious dogs. He tries calling out to him desperately to run, only for Bambi to not respond.
It really hammers home that the deer, and the wild animals in general, don't understand what Man really is: another predator. Because none of the others use tools or weapons. But Man doesn't have claws or sharp teeth or strength or speed. They have their brain. And that has elevated them to a threat beyond the deer's understanding. They can kill from a distance, or mimic their dead loved ones, or mask their scent, or send other animals after them, and there's nothing the deer can do but hide and pray. Because there is no escaping Man in the end. He'll always come back.
When Mena is caught in the snare and hunting dogs begin closing in. Bambi meanwhile has locked up in terror from the sight of man like before, with Mena unable to break free and protect him, begging and screaming for him to run as the dogs get closer. Even when Bambi snaps out of it, it only intensifies as he decides to turn back and pull a Heroic Sacrifice and lure the dogs away from her.
Both of Man's appearances are signified by frantic birds flying away and giving a creepy distorted crow that sounds like a mix of a bird call and a human cry of "MAAANNN!".
During the final chase, Bambi tries to hide in the tall grass. All we can see are lumps of grass rusting where the dogs are searching and closing in on Bambi as he waits terrified. The near silence of the soundtrack as this happens only makes it more intense.
The moment where the final remaining hunting dog confronts Bambi on the cliff. The dog looms over him, teeth bared, lightning flashing... brrr. To give you an idea (because it's scarier in animation), look at the page image. Thankfully, it then turns into Awesome when Bambi bucks it off the cliff.
A lower key example, but Ronno emerging from the bushes to harass Bambi after being taken by Mena. Unlike his previous pompous taunting for most of the film beforehand, Ronno's goading comes off more sinister and closer to real life bullying, cruelly taunting Bambi till he finally snaps and gives him the vicious battle he wants. This gives a creepy allusion to the more bitter and terrifying presence he takes on as an adult shown in the first film, and it's only more unsettling since he's still just a child.
Ronno: Hello Princess...
What makes the fight even more unsettling is that it's a shot for shot recreation of the fight they have in the original movie.
Ronno gets increasingly more vicious as the fight continues. At one point he has Bambi down he tries to grind him under his hooves as he tried to in the first film, leaving a nasty engravement on the ground where Bambi's head was a second before. After Bambi floors him twice, Ronno goes completely apeshit and bucks him viciously from behind with no regard for Mena in front of him. The last shot of the fight before they are distracted by the hunting snare going off is Ronno pinning Bambi to the ground ready to stomp him again in a rage. While this was conveyed as standard animal practice in the first film, the more humanised treatment of the midquel makes it more clearly a vicious extremely frustrated little kid trying to brutally harm the target of their scorn.
The entire film, when looked from the Great Prince's perspective, is packed with parental worries. His mate is killed by hunters—a mate who he seemingly never spent much with because of his duties as Prince, which must play on his mind. But he doesn't even get the chance to grieve properly for her: he has to focus on his responsibilities to the herd as well, and tries to grieve by not mentioning her at all and shutting Bambi down any time when Bambi mentions his mother. He's new to being a parent and can't seem to connect with his son. Just days later, his young son—the only thing he has left of his beloved mate and a son who he loves in his own way—is lured out into the open meadow, freezes while dogs get close to him. The Great Prince only just manages to fight them off and even his lecture towards Bambi shows just how scared he was. Then, when he finally manages to bond with his son, Friend Owl introduces Mena and Bambi is so sad that he wishes his father dead. His son leaves with Mena—minutes later, he finds Mena trapped with dogs chasing after his son. And when all seems fine and Bambi's defeated the dogs, Bambi falls off a cliff and seemingly dies. The Great Prince is obviously heartbroken—he just can't catch a break.
. The call does a spot-on imitation of Bambi's mother (and it's a creepy, gentle repetition of "I'm here...It's me...Hello...") which combined with Bambi's last shred of hope of seeing his mother alive again, almost gets him mauled by a pack of hunting dogs and shot. He's literally paralyzed with fear when he sees the hunting dogs on his way.