Since Voldemort rose to power, the security around Nuremberg Castle was tightened. There was a fear that the Dark Lord would recruit his predecessor of "World's Darkest Wizard" to his cause, or seek his council.
But they needn't worry. Voldemort was far too dark and cruel for Grindelwald's liking. Voldemort tortured and killed for the fun of it, while Grindewald tried to only kill when he felt like it was the only option. Still a bad person, but not as bad. Also, Voldemort was super arrogant, and wouldn't dream of sharing power.
All this made it more difficult for Dumbledore to visit him and gain his council. However, Dumbledore wasn't one to give up so easily. So, he found a way.
Knowing that he couldn't use his patronus, since it was so unique, he instead used his influence and power to learn all of the new measures the Wizarding world was taking to secure their top prisoner. Then, he found workarounds.
Grindlewald leaned against the cold stone of his cell. He was so bored. Suddenly a red and silver Phoenix appeared by his window.
The old man smiled. "Knew you'd find a way."
The Phoenix smiled. Then he flew inside and looked around. A concerned look appeared on his face.
"I know." Gellert replied, "Very restrictive." He then gently offered his arm to the magnificent bird.
The Phoenix stared at it, as if deciding weather or not it was a good idea. Eventually, it hopped on, and Grindlewald carried him to a corner, where he sat down. With a flick of his other hand, a magical barrier formed around them. It was small, but it was enough.
"Try as they might, they aren't very good at disabling wandless magic." The grayed blonde explained.
The Phoenix nodded, then made his way to the floor, where he transfigured into Albus Dumbledore. "That is the hardest to contain." He added. Sometime in his youth, Dumbledore had semi-legally become an Animagi. He had planned on registering himself, but had never gotten around to it. He was certain the Ministry was somewhat aware, but had never bothered to hound him. Afterall, there were bigger matters to worry about, and he was sure it was forgotten about. "And I remember you being excellent at it."
A small smile crossed Grindlewald's face. "As well as you."
Dumbledore also nodded. There was a pause before he said, "Have any new Visions?"
Grindlewald nodded. "Divination will need a new professor."
"Divination's a useless class." Dumbledore curtly replied, "Only useful for Seers, and those are few."
Grindlewald nodded again, "You will keep the class. The replacement will be an... odd woman named Sybill Trelawney. She's a Seer, but she's terrible at interpreting what she sees."
"Then why would I hire her?" Although the old wizard was not above hiring the incompetent to expose them, he saw no value in hiring a Seer who's only fault was that she couldn't interpret her Visions.
Grindlewald smiled. "Because she will deliver a prophecy that will put her in grave danger, but she won't remember it. Only the two of us will know the full prophecy. The Dark Lord will know the first part."
Dumbledore thought for a moment, taking it all in. Finally he said, "And how will Tom know this information?"
Grindlewald paused for effect, "Severus Snape."
"Severus?" Dumbledore knew the boy hung out with a group of bullies, and had even taken part in their bullying. But it seemed to mostly fit in, or to seek revenge, even if the boy enjoyed it slightly.
"Yes." The reformed dark wizard replied while nodding, "However, that information will lead to Lily Evans being put in danger. And the guilt the boy will bear over putting his beloved in direct threat of death, will make him switch sides."
"Love is powerful." Dumbledore noted, suddenly recalling the first summer he and Gellert spend together. He didn't like it. Remembering that summer reminded him how easy it was for him to be tempted to the dark side, how blinded by love he was. How desperate he was for purpose that he was willing to become a dark wizard.
"Indeed." Grindlewald replied. "All you need to do to keep Snape loyal to you, is to remind him of his love for Lily Evans. The guilt he feels over losing her and putting her in danger will be enough for him to renounce the Death Eaters and all they stand for."
Dumbledore nodded again. He was going to ask what the prophecy in question would be, but he knew his ex wouldn't tell him. There were some things he had to figure out as they happened.
"I must say, Snape will make a fantastic double agent." Grindlewald said, breaking the silence, "Remember what I said about him and occlumency?"
"Yes." Dumbledore answered. He remembered his ex telling him all about the talented Severus Snape, Lily Evans, and the Marauders. He knew that three of them were illegal animagi, and it was from Grindlewald that he knew of Remus Lupin's lycanthropy. He also knew, from Gellert, that Lily Evans would use Sacrificial Love to cause Voldemort's first defeat.
Gellert nodded. Suddenly, Albus became all too aware of the tight space they were in. A deep blush started to appear on his old weathered face as he started to wrestle with old feelings that suddenly burst forward. He hated moments like this.
Gellert leaned in slightly, "Space getting to you?"
"A-a little." Albus nervously answered.
Gellert chuckled. "Perhaps a game of cards will take your mind off things?"
Albus shook his head. "Why do you do this?"
"These days it's for fun." Gellert cheekily answered, "You are pretty much my only visitor."
Dumbledore let out a huge sigh. He hated doing this, but he needed the information. Also, no one deserved to be lonely, even if they started a war. Begrudgingly, he took out a deck of cards. "You're not making this easy."
"I try." Gellert replied, then the two played Go Fish.
