This is just part 1!
The Elder Wand is one of three objects that make up the fabled Deathly Hallows along with the Resurrection Stone and the Cloak Of Invisibility. According to “ The Tale of Three Brothers ", it was the first Hallow created, supposedly made by Death himself. It was bestowed upon Antioch Peverell after he requested, as his bounty, a wand worthy of someone who had outsmarted Death.
It is said to be the most powerful wand that has ever existed, able to perform feats of magic that would normally be impossible even for the most skilled wizards, such as mending another wand damaged beyond normal magical repair.
The Elder Wand's core is the tail hair of a Thestral, a potent yet tricky substance to master; only a witch or wizard who is capable of accepting death can do so, since only by them can a Thestral hair even be seen.
Egbert the monstrous
Dumbledore says the main reason the Elder Wand has become so powerful is that it’s spent centuries accumulating power and experience from many masters.
“Believers in the Elder Wand, however, hold that because of the way in which it has always passed allegiance between owners — the next master overcoming the first, usually by killing him — the Elder Wand has never been destroyed or buried, but has survived to accumulate wisdom, strength, and power far beyond the ordinary.” - The Tales of Beedle the Bard
Though the Elder Wand may or may not have been somewhat more powerful than other wands at the point of its creation, likely the main reason it’s so powerful is that it’s absorbed experience from very many powerful wizards for centuries of use.
Though it is a powerful wand, the Elder Wand clearly isn’t unbeatable as its owners have been beaten several times throughout history, as Dumbledore points out.
“What must strike any intelligent witch or wizard on studying the so-called history of the Elder Wand is that every man who claims to have owned it has insisted that it is “unbeatable,” when the known facts of its passage through many owners’ hands demonstrate that has it not only been beaten hundreds of times, but that it also attracts trouble as Grumble the Grubby Goat attracted flies.” - The Tales of Beedle the Bard
This is much as I know about The Elder Wand. I hope this helps you understand more about it.
Your suggestions are welcome in the comment section.