Now that it's been confirmed that King Riku is alive, we aren't that far away from learning how Doflamingo usurped him. In other words, it's theory time!!
For this, I see two possible scenarios at the moment, but not necessarily the reasoning behind it.
1st scenario: Doflamingo used his Strings to control King Riku, in order to command his forces to burn down the village. This, in turn, would help set up Doflamingo as the white knight(like the knight his name comes from), coming in to save Dressrosa, thus gaining their trust.
2nd scenario: King Riku decided to burn down the village, himself. I can't see any reasoning behind it yet, but right now, from what we've seen, that's what the chapters support the most.
If you take a look at this page, the citizens are saying that Riku and his forces set fire to the village:
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In this page, Tank mentions that Riku had to make a hard choice:
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In this page, we see all the former soldiers, and people that have been turned into toys, bowing down to the King. As that fodder guy says, he believed that the citizens despised him:
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From these two pages, it seems to me that King Riku decided to burn it down, for whatever reason, and his former soldiers supported him in doing so. The way they all still support him to this day, if the 2nd scenario is the case, then there was probably a greater plan behind it.
But in this page, Tank mentions that King Riku suffered a great tragedy that day:
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And here, Toy Soldier mentions that King Riku only did what he thought was best for his country:
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So what I think happened is simply that King Riku's plan, whatever it was, failed. And also, maybe his wife was killed that day, hence the great tragedy.
So what are your thoughts? Do you have any theories on this, maybe what his plans were?
Edit: And by the way, right after posting this, I realized no one has really mentioned that they don't believe King Riku burned down the village
I think that Riku had to burn down a lot of the kingdom in order to try and deter Doflamingo from coming. Citizens hate him because they think he was going on a murderous rampage when he really had the future of the island in mind.
