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One Piece 749 Spoilers - Predictions and discussions
One Piece 748 has been released.
How many chapters before the fight against Doflamingo starts? At the pace this is going I'm inclined to say about 20-25 ... It seems like the chapters now follow a simple pattern: 
 
Luffy and co team trying to get to mingo 
Mingo says something 
Fuji says something 
1-2 panel clash 
Rest of chapter dedicated to other colosseum gladiators and "funny" moments 
the end 
 
next chapter: 
Luffy and co are still trying to get to mingo 
Mingo says something 
Fuji says something 
1-2 panel clash 
Rest of chapter dedicated to other colosseum gladiators and "funny" moments 
 
Chapter 769 
Luffy and co are really close to mingo 
Mingo says something about riku 
Fuji something something civilians 
Barto's epic "wow strawhats so awesome!" moment 
1-2 panel clash 
Rest of chapter dedicated to other colosseum gladiators and "funny" moments