Before I get into my reply I just want to highlight something Garo said which I completely agree with.
I do not believe this conflation of "dark" and "mature" should go on any longer.
'Dark' does not automatically mean 'mature' and vice versa.
Anyway, I voted for 'Other' because, again, agreeing with Garo, the other options do not automatically make something mature either. Death can be a tool to add maturity but the event of death itself is not what does that. The way other characters respond to and deal with death is where maturity would enter into it. Throwing in some deaths won't make a game mature unless they have meaning and can, as Garo pointed out, be seen as immature if they don't.
A wonderful example of this would be the novel
Harry Potter and the Deathly Hallows. J.K. Rowling totally mishandles the concept of death in that book. Lord Voldemort himself directly murders over ten people, many of which we never see or have never heard of, like Gregorovitch the wand-maker. Because we have no connection to these events we have no emotional engagement and so they are ultimately pointless. Furthermore, the fact that all Lord Voldemort actually does throughout the entire novel is kill people for no real reason devalues the threat of death, turning it into something the reader no longer fears but expects. There is one point in the novel when the author has to literally bring a character back from the dead just so that they can outright explain the significance of their death to the reader. It's very jarring and takes you out of what should have been a tense and dramatic moment. By just throwing death in for the sake of death, Rowling managed to make all of it ultimately worthless, because it doesn't do anything for either the plot or the characters.
It's like when DarkestLink mentions Mikau from
Majora's Mask. We'd only just met the character and knew nothing about him, so when he died we weren't going to feel anything about it because there's no connection. He just dies because Link needs to get a Zora Mask, that's it. Compare that to the Deku Butler's son. Although he dies before the game even begins we get to see how it affects the Deku Butler and how he deals with it emotionally. When we see him crying in front of his son's corpse during the credits its a very bittersweet moment since everyone else in Termina is rejoicing how everything is better for them while the Butler has lost that which he cares about most. It's not much, I admit, but it's a more mature moment than the death of Mikau because it has some meaning and makes us feel an emotion.
Death could help make a
Zelda game more mature, sure, but the point is death for death's sake won't do it. There has to be somthing more behind it, some significance to either plot or character development or just the player's emotional investment. We have to have a reason to care about death before death can add maturity to a game. The same can be said about romance. Throwing two characters together romantically doesn't mean anything if there's no engagement with the audience. I want to use the example of Alyx Vance and Gordon Freeman from
Half-Life 2 for this point. From the moment Alyx meets Gordon until the end of
Episode 2, Alyx has never once heard Gordon say a single word. Not once. He has never actually interacted with her in any way whatsoever except staring at her every now and then. The excuse of "But we have to imagine what Gordon is saying to her" doesn't hold up when the game itself openly acknowledges the fact that he does not speak to her ("Not much of a talker are you?"). She has no reason to feel anything close to love for this man who acts like a machine. He never speaks to her, he never gives any input on plans or activities, he never seems happy to see people and he goes off without hesitation whenever he is ordered to go somewhere and kill a bunch of people. In the reality of the game, he would come across as an unhinged psychopath with no personality or humanity. And we are expected to believe that she is falling in love with him purely because they shot some people together a few times.
There's no reason to believe that a romance is developing between these two characters and we only get to see and experience one half of it any way. This makes it incredibly difficult to engage with it because it doesn't feel real. We can't understand why Alyx would like Gordon and so we disconnect. There's no reciprocation of emotions, there's no drama about it, it's just something they threw in and hoped would work but it doesn't. The player may see why Gordon would be attracted to Alyx but there's nothing happening when we consider why Alyx would like Gordon. This can be applied to
Zelda too. I have never once felt that there was ever an attempt at a romantic sub-plot in a single
Zelda game because Link is never shown to really interact with other people.
Skyward Sword was a better attempt at including such a story but, again, the nature of Link's silent character means that we see him interact very little with Zelda herself and the entire relationship is guided exclusively by her and her actions. Again, we have a situation in which we can see why Link would like Zelda but not why Zelda would like Link. We don't see the relationship grow or develop and we can't do anything about it either, so it's difficult to get emotionally invested in it.
Mass Effect does romance much better because it is guided by the player. You interact with your crew on your terms and, as you do, you develop real connections with people. Yes, a lot of people will have gone down the romance route purely for the... *cough*... 'romantic embraces' towards the end but if you go into it trying to just put yourself into that universe instead of working towards a specific goal you'd be surprised by what you get out of it. I'm one of the few people whose main
Mass Effect avatar was a female Shepherd and in the end my Shepherd ended up falling in love with Garrus. This was one of the better parts of the game because Garrus was my favourite character and seeing that bond form between player and character was very rewarding. In this way, the concept of romance was used not to titilate or garner attention but to get the player invested emotionally and engage with what was happening.
Danger and violence also don't maturity make but I shan't go on another three paragraph ramble about that. Maturity comes from themes and engaging with the audience. If you feel a connection to what's happening or to specific characters then the game can be described as mature.
Braid is a very mature game, for example. I almost cried when I played it because it made me consider choices I had made in my life and filled me with a deep feeling of regret. It achieved this with bright colours, a 'plot' that was disjointed and not real and an extended reference to the humour of Monty Python. The theme of
Braid was reflection and regret and the central puzzle mechanic of rewinding time underlined that superbly. In the end, I had an emotional experience, rather than just being broadly entertained for several hours.
The reason why I voted for 'Other' was to point out that video games can be more mature in really simple ways too. As an interactive media, video games can actually achieve a degree of maturity by simply respecting their audience.
Modern Warfare 2 opens with a slow tutorial about how to walk and how to aim your gun. It's simplistic and idiotic and it makes no real sense in the context of the game. It is an example of the game treating its audience like a child, a decision made all the less understandable when you consider that the games are rated for adult players only. Yes, children play it but its target audience does not need to be treated that way.
Skyward Sword would be an example from the
Zelda franchise. The character of Fi was nothing but a hand-holding guide whose only purpose was to make sure that you never had to wonder what to do next by giving you all the answers. In this way, the original
The Legend of Zelda was a more mature video game than more recent entries because it left players to figure things out themselves, to try things out, experiment, explore and learn about the game they were playing.
Death and romance and violence, yes, they can all make a game more mature but not by themselves. There has to be something more to them, some reason or meaning, that gets the audience emotionally involved. Having those things for the sake of having them is not mature. Video games also have the ability to display a level of maturity by not treating their audience like babies who need to be trained in order to play a game. People are intelligent and can learn and understand things by doing. A
Zelda game which left us on our own a lot more would be somewhat more mature by that aspect alone, if you ask me.