Thread:Hydregion/@comment-24873366-20140501165407/@comment-11454852-20140501170939

Basically. each world focuses on:

Dragon: Kagero-like, oversupported and focused on monster destruction, they also increase the gauge to cast expensive Impacts to finish the opponent. Themed after dragons and knights riding dragons.

Danger: Beatdown with high power monsters and get rewards from having the center open and/or having an item equipped. Themed after armored creatures based on mythological creatures and the Duel Dragons.

Magic: Control the speed game with powerful skills and many spells. Themed after Demons and Wizards.

Katana: Predict the opponent's moves, increase hand advantage for several uses, and hide cards face down to use them as counters. Themed after Ninjas and undead creatures.

Ancient: Very powerful Size 3 monsters with the very risky Lifelink Keyword. Themed after Dragons too.

The exact focus can vary depending on how you build the deck and what archetype you use.