You can implement stamina for guns via afflicting certain gun mechanics. For example, a lower stamina would result in increased recoil, inaccuracy, or dampened ADS. Melee combat and stamina have a very special relationship in videogames that feature them in that the distribution has to be just right: actions, spending, and weapons need to have fluid or at least reasonable stamina allocation Gun-wise, the stamina system wouldn't work. In that context, Destiny doesn't really [i]need[/i] stamina or mechanics that make gunplay any more difficult than it really has to be. It doesn't need any more game mechanics than it should because it would detract from what's important at hand: solid gameplay. Melee-combat is more understandable because it seems to be an inherency with many in-depth melee system. However, if we take a look at the little gameplay we've seen of melee combat, such as the hunter using her knife, we can see that it's very fast, sharp, and precise. It appears to be a skill but to me it sets up the tone of melee combat. The reason why it worked in games like Skyrim and Dark Souls is because the gameplay was integral to stamina, but Destiny in all honestly appears to be going for a very fast-paced foundation. As for movement, that's totally up in the air to me. Things like sliding, gliding, blinking, even abilities if it doesn't have it's own separate meter: I don't really have much of an opinion on yet, however I can still acknowledge that they're validate topics.