Thanks for an outstanding response to the puzzle!
This was not an easy puzzle. I got the correct answer from The trio of Ashish+Arushi+Ishir, as well as Shruti Mittal, who did a great job of solving the puzzle with the required trick. Anisha and Arushi also solved the puzzle but with a lot of hints…but well done all of you!
The basic trick to cracking the puzzle is that whenever you have 2, 4, 8, 16, or any power of 2, it is the first one who wins. When you have 1500 people, you look for the closest power of 2, which is 1024. Difference between 1500 and 1024 is 476, which means once 476 people have been killed, whoever has the sword will win. 476th person to be killed will be 476 x 2 = 952, which means at that point 953rd person will have the sword and will win. Answer is explained for children in more detail on this video:
Hope you enjoyed the puzzle!