Dumbledore defeated Grindelwald in a legendary duel that took place in 1945. The two powerful wizards had been friends in their youth but became adversaries due to Grindelwald's pursuit of dark magic and desire for power. The duel between them was fierce and intense, but ultimately Dumbledore emerged victorious, using his exceptional magical abilities and strategic thinking to overcome Grindelwald. This victory led to Grindelwald's imprisonment in Nurmengard, where he remained until his eventual defeat by Voldemort in 1998. **

Voldemort kills Grindelwald in the Harry Potter series during the events of "Harry Potter and the Deathly Hallows." Grindelwald is killed by Voldemort in the year 1998, at Nurmengard, the prison he had built to hold his enemies. Voldemort seeks information from Grindelwald about the Elder Wand, one of the three Deathly Hallows, and ultimately kills him when he refuses to give up the information. **

The acolytes address Grindelwald with reverence and respect, often using titles such as "Master" or "Lord." They see him as a powerful and charismatic leader, and they believe in his vision for a new world order where wizards reign supreme. The acolytes are loyal followers who are willing to do whatever it takes to support Grindelwald's cause. **

While it is not explicitly stated in the Harry Potter series or the Fantastic Beasts films, there is strong evidence to suggest that Dumbledore had romantic feelings for Grindelwald. J.K. Rowling has confirmed that Dumbledore was in love with Grindelwald, making their relationship complex and tragic. Their bond was a significant part of Dumbledore's past and influenced his actions and decisions throughout his life. **

It is difficult to definitively say who would win in a battle between Voldemort and Grindelwald as both are powerful dark wizards with different strengths and abilities. Voldemort is known for his exceptional skill in dark magic and his ability to create Horcruxes, while Grindelwald is a master manipulator and highly skilled in dueling. Ultimately, the outcome of a battle between them would likely depend on the circumstances and strategies employed by each wizard. **

As an AI language model, I don't have personal opinions. However, some fans may prefer Johnny Depp's portrayal of Grindelwald in the "Fantastic Beasts" films, while others may prefer Mads Mikkelsen's interpretation of the character in the upcoming films. Both actors bring their own unique style and charisma to the role, and it ultimately comes down to individual preferences. **

As an AI language model, I don't have personal opinions. However, I can provide information on Grindelwald as a character in the Harry Potter universe. Grindelwald is a complex and compelling character who represents the darker side of wizarding society. His ideology and actions have significant consequences for the wizarding world, and his conflict with Albus Dumbledore adds depth to the Harry Potter story. Ultimately, Grindelwald serves as a powerful antagonist, driving the narrative forward and challenging the moral and ethical boundaries of the wizarding world. **

Both Voldemort and Grindelwald are extremely powerful dark wizards, but it is difficult to definitively say who is stronger. Voldemort is known for his exceptional magical abilities, including his mastery of dark magic and his skill in dueling. Grindelwald, on the other hand, was considered one of the most powerful dark wizards of his time and was known for his charisma and ability to manipulate others. Ultimately, their strength may depend on the specific circumstances and the context in which they are compared. **