I finished Assassin’s Creed 2 not too long ago, and just recently a friend lent me Prototype. Both games have been very enjoyable, especially from the perspective of free navigation of space and the development of an increasingly diverse and complex arsenal of player abilities. In terms of play, the difference that stood out to me the most between the two games is how progress is implemented within the narrative of the story world. Progress in Assassin’s Creed 2 (AC2) is entirely diegetic, whereas progress in Prototype is almost entirely extradiegetic. I found the diegetic development in AC2 to be extremely rewarding, but the choose-your-own ability system in Protoype is also compelling for different reasons. The approaches offer the conflicting goals of narrative integration versus configurability. What approaches could we employ to integrate the desirable features of both systems?
Progress in AC2 is diegetic. This means that the protagonist Ezio gains a new ability when it is granted by the story. The player has no control over what abilities are learned, but each ability is integrated into what is happening in the story world. For example: Ezio gains use of the hidden blade when it is given to him, Ezio learns how to use special maneuvers with other weapons when the player purchases a lesson and Ezio is taught. Every new maneuver (with only a couple exceptions) learned is given by the plot, so the player has no control over the development of progress, it is entirely controlled by the designer. A major positive of this is that challenges are presented to the player explicitly to draw the use of the new skills. Very rarely is the player up against an adversary or obstacle for which there is no way around.
Prototype takes a very oppositional stance: Almost every new ability learned is through an interface in the menu. When the player has accumulated enough of the game’s currency, new skills may be purchased and used immediately. Skills are unlocked as the plot wears on, but typically (or at the very least, in my experience), there are many more skills available than can be purchased. This allows the player to control the repertoire of abilities that the protagonist, Alex Mercer, can use. The player may have a preference for one power over another, and focus development of new abilities on that preferred power. This is empowering to the player to be able to customize and develop the skills usable in the game. However, a tradeoff is that there is no story world explanation as to why Alex develops his newfound abilities. A consequence of this is that there is also very little in-game instruction as to how to use the abilities. Because of the design, a tutorial system would be awkward to develop: The player will not necessarily want to sit through five tutorials one after another after purchasing five new abilities. Because the player can learn abilities anywhere and at any time, there is no way to make sure that there is a suitable way of explaining the abilities after the player learns them. The result (again, for me) is that Alex has a mess of abilities and the player has no way to clearly understand how and when they can be used.
Diegetic progression is useful for both the purposes of instruction and also for the sake of making the player’s progression seem meaningful in the story world. However, diegetic progression often leads to restrictive development of gameplay. It seems like there should be some form of compromising between diegetic progression and character customizability. I would argue that quest based ability gains would be a good way to mediate between these. Another possibility is to use a clear training system, much like in Okami, to let the player learn new abilities, but also be able to practice them at leisure.