Preparing for the "Van Kanegem" tournament.

In reality, a player who places high in one of the versions, especially with a large number of participants (as is likely to be the case in the third stage), has a significant chance of achieving a high overall result. For example, a player who wins two stages with 10 players each will receive at least 366 points. Meanwhile, a player who plays all stages but consistently finishes in last place in terms of time (even if they are in first place in terms of resources and development), with the same regular 10 participants, will score a maximum of 210 points. The difference is obvious.
No one is forcing anyone to play in all stages. It's simply that you can receive additional points for the mere fact of participating and submitting results, while focusing all your efforts on the version where you are particularly strong. Each stage is an independent tournament, with its own winners, etc. But the entire "Van Cunningham" tournament is a single concept.
The "Circle of the Sword" implies starting the game with the Castle of those whose strength lies in the sword – Humans, Barbarians (for example). The "Circle of Magic" correspondingly implies the Castles of the Sorceress, Necromancer, etc. And so on.