Creeper League (Survive in a world with many other crafters!)

How good would a league be, where you can fight with many of the other players in just one world? 2000 players? Minecraft Worlds are infinitely big, so you can contain many players in them, that can slain others. The prize, for for example kill the most player, can be Minecoins, or can be a real trophy that say "I'm #100 in Minecraft!"