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:
Consumable Items present an excellent way of modifying the difficulty of a game to assist players when they need it most, without going through a menu and choosing a different level of difficulty from a list. This also nicely solves the "ego problem" certain players face where they won't want to play on easier difficulties because they see it as admitting defeat. Consumable Items will be defined as "any item which is deleted from the player's inventory on use to invoke a temporary effect".
Consumables can be used to temporarily bump up the difficulty too!
The core of what makes Consumable Items so useful is the player's ability to trigger them at will. In my game, Robo's World: The Zarnok Fortress, I included "Spare Parts" which the player could collect throughout the game, then use to replenish Health, Shield Power-Ups and Grenades.
Zarnok Fortress even features an auto-crafting system to instantly redeem Spare Parts as necessary
The means by which the player acquires the Consumable needs to be weighed against the challenge that is being overcome. Typically, you should be trying to balance things so that instead of doing one thing that is of X difficulty, the player is instead tasked with doing something of Y difficulty Z number of times so that they add up to being roughly equivalent. Whether the tasks are exactly equivalent mathematically or whether they add up to slightly more or less than the other task must be determined by the nature of the game you are creating. If it falls too low, players won't want to choose option X, when the combination of Y and Z is easier, whereas if it is too hard, the alternative will feel like grinding and players won't enjoy that either.
Many Free to Play games tap into this; allowing the user the ability to purchase power on demand with micro-transactions
Item usage gives players a very potent means of modifying the difficulty in your game and means you really need to think through the nature of the challenges in your game and how each of them can potentially be effected by all the various items players can store in their inventory.
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