Totem of War

When a player is killed, they drop a Totem Shard. Having a Totem Shard in you inventory gives you effects to increase you speed. You then can use six Totem Shards to create a Half Totem. You then can use two Half Totems, one Dragon Egg, and two redstone dust to make a Totem of War.

Having the Totem of War in your inventory will make you quite a match in any pvp senario, but it has it's downsides. It will leak you cords in chat every so often.

You can also craft a Dragon Egg using a Totem of War.