New theory on how Teach can be the final villain:
Somehow, Saturn will end up being defeated/killed/imprisoned during the events at Egghead, but Borsalino and the others won't be aware. Devon will disguise herself as him and return to Mary Geoise. Or, alternatively, Lafitte will hypnotize Saturn.
Kuzan will defeat Garp. Capturing Koby was part of a plan to bait Garp. Teach will make a deal with the WG to imprison/eliminate Garp in exchange for becoming king. Sengoku mentioned that the government wanted Garp eliminated because of his insubordination to the Celestial Dragons. This is the perfect opportunity for them to get rid of an insubordinate and powerful soldier, and a D as well.
Devon/Saturn will invite Teach to Mary Geoise, and Teach and his crew will defeat the 5 Elders, and kill Imu and steal his fruit.
Then, Teach will sit his fatass on the throne and become King of the World
Thoughts?
@Jailer @Erkan12 @Blackbeard @SakazOuki @Blother Fertitta