The following article contains my Extended Thoughts on "Difficulty" discussed in the Gameology podcast with my co-host Mathew Falvai. You can listen to the Podcast via RSS, on iTunes, Google Play Music, or watch the episode in video format:
The Problem of Open World
When you give a player the choice of which part of the game they wish to tackle first, (letting them pick a Dungeon or Robot Master) it means that each of those zones must be equally difficult to begin with and follow the same difficulty curve within each stage. Depending on how the difficulty is balanced, this can have one of two results. If every stage is balanced towards being a viable entry point in the game for the player, then it will not present enough of a challenge as the player tackles the last few stages. This can be made worse if the player is picking up a stat-boosting item somewhere in each stages that further reduces the difficulty of later levels. Alternately, the difficulty can be balanced towards late-game play and it presents a difficulty spike which turns early-game players away, which I would argue is the worse alternative. In the second case, if the player gets a stat-boosting item in each stage, it effectively creates a backwards difficulty curve as each item the player gets makes the game easier! Even if the balance falls somewhere in the middle, that would just mean your are alienating both early and late-game play experiences.
The way I chose to tackle maintaining a balanced difficulty experience within an open world in Robo's World: The Zarnok Fortress was with a mechanic in the game where the enemy's intelligence level steadily increases. This way, at the outset of the game, the enemy intelligence would be low, making for an easier play experience. As time went on, the AI level would go up, matching the player's advancement and providing a consistent level of challenge. Essentially, you need to have some factor in your game, likely a (multiplier) which can be cranked up over time in time with the player's progress through the game.
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