What order should I play homm3?

The official campaign order in release order goes Restoration of Erathia -> Armageddon’s Blade -> Shadow of Death despite the campaign menu listing these in the opposite order.

then, What happened to docent Picolan?

We have suffered a grievous loss. On November 7, 2020, the founder and leader of the Horn of the Abyss project, wonderful artist and composer known to the wide HoMM community as Docent Picolan, died tragically. … Not only was Docent the project manager; he was also responsible for a huge amount of graphical assets.

hence, Which homm3 campaign was first?

Chronologically SoD is first. But subjectively by my opinion, RoE campaigns ,followed later by AB, are natural choice for start. They are created for drawing you into the story gradually.

indeed

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