World Beyblade Organization by Fighting Spirits Inc.

I tried searching for this but I couldn't find it. List your most useful part please.

It can basically be discussed here, since a part alone does not do much :
http://worldbeyblade.org/Thread-Strongest-MFB-you-have

By the way, threads should only be made if they have discussion value. Listing the most useful parts you have stops there, and involves no participation from other parties.