There was an RPG Maker game called Forum Fantasy which did use instant death as a means of telling a joke. I.E. It was obvious, saving was a non-issue, and there was always this sense of 'wow, you died an obvious death. congrats' feel that was never demeaning. You'd walk down a hallway covered in blood, push a button, and die. It was out of the way, there was nothing really there except a button, and it's made very clear that it will kill you. Still made me chuckle.
That being said, there was an instance of it being used to rather shocking effect, considering the otherwise funny instances of it being used. Such as going down a hallway to read a sign, it reading, 'Don't look behind you'. You expect a jumpscare, but you don't expect to outright die from Slenderman (this being, of course, a RPG version of the internet). Another, somewhat more shocking one, is when the ghost of a little girl kills you (plays with you, by skipping rope with your guts) because you didn't help her burn her body, and thus help her find peace in the grave.
That being said: Instant death should never be a feature, it is always a consequence. As a developer, you should always strive to have instant death be as a result of a legitimate mistake, and not a happenstance that technically could have been avoided, but happened because the game decided then 'Eff you.'
Dark Souls, as a series, has some moments where instant death does ratchet the tension, but can also result in rage because of the circumstances. The Bed of Chaos boss has bottomless pits and wonky hit boxes, and platforming aspects to the battle that are not great. You miss a jump, or an arm sends you flying into a pit, or both happen at once, and you're just left feeling increasingly agitated.
In Anor Londo, there are a pair of enemies that will snipe you if you're not careful. For a new player, it is a prohibitively difficult section of an otherwise interesting location, and being unable to figure out how to get past a specific enemy the right way will lead to yet another stupid death.
In DS2, the Old Iron King has a small arena surrounded by lava, there is one hole in the floor in a place the player will likely not see. It is often joked at how that hole is the true boss of the Iron Keep, because of how many players have either walked into it or have been knocked into it. An actual otherwise good implementation of instant death as a danger, but that one hole just does not have a reason to exist in the form that it does.
While the threat of instant death via environment can be an effective tool for tension, it is often overused, like jump scares, in horror games. Particularly RPG Horror games. In my experience, there are too often instances where it's more of an annoyance than something that drives fear. Being chased by a monster that will instantly kill you? Thrilling! Terrifying! Provided the level is designed well enough and escape is relatively easy.
Examining an item kills you, you restart, you examine another item, it also kills you, you restart... Not scary, annoying.
A monster will kill you instantly, or at least severely cripple you if you touch it without a defensive item? Terrifying, especially if there is a limited supply and few ways to actually kill the enemy. Actually pretty scary, because you know you can take a hit or two, so long as you have the requisite item. But without that item, it's just difficulty for difficulty's sake.
There was also another, extremely aggravating example in a horror RPG Maker game for Android. The game was free, but you had limited lives that recharged in real time, essentially, an energy system a la facebook game with associated microtransations. Glorious. The particular section I am referring to is where you have to race across a room, grab an item, and get the hell out of dodge before you died instantly. The timing was ****ing precise. And with only three lives and literal hours to wait for another one, it took me days to get past because I often died a single tile away from leaving the room. It was scary and tense at the beginning, and surreal as heck, but the more I died to this one, single area, the more I just got angry. I did manage to beat it, it was possible to beat, but boy howdy did it feel like an explicit way to try to get me to spend money on extra lives.
Yes, the threat of death is a useful tool for creating tension, if used properly and sparingly. the Doom status as seen in Final Fantasy, Petrify, being removed from battle, these are useful tools for generating tension in a battle. Doom literally counts you down how many turns you have to kill the enemy, and can also be good for resource management gameplay. Similar with Petrify, which you need to heal or your party could be effectively instantly killed. In FFX, being attacked again could remove that party member for the rest of battle. Getting blasted out of combat can also be useful, provided the player can counter it effectively and consistently.
Ultimately, it comes down to how you balance this threat of death with the player's ability to do something about it. Falling in a pit will kill you, so avoid them. This monster is chasing you, leave the area to escape it or die. This on-field enemy will kill you unless you have an item that stuns it (which you could even add a place to obtain more, yet limited amounts, of these items technically infinitely), you must solve this puzzle within X minutes or be crushed, you need to reach the end of a room, grab an item, and leave before a nursery rhyme finishes (Seriously, don't do this if you use microtransations + limited lives. Just don't.), there are so many ways you can use it, but you need to use it sparingly.
That being said, there was an instance of it being used to rather shocking effect, considering the otherwise funny instances of it being used. Such as going down a hallway to read a sign, it reading, 'Don't look behind you'. You expect a jumpscare, but you don't expect to outright die from Slenderman (this being, of course, a RPG version of the internet). Another, somewhat more shocking one, is when the ghost of a little girl kills you (plays with you, by skipping rope with your guts) because you didn't help her burn her body, and thus help her find peace in the grave.
That being said: Instant death should never be a feature, it is always a consequence. As a developer, you should always strive to have instant death be as a result of a legitimate mistake, and not a happenstance that technically could have been avoided, but happened because the game decided then 'Eff you.'
Dark Souls, as a series, has some moments where instant death does ratchet the tension, but can also result in rage because of the circumstances. The Bed of Chaos boss has bottomless pits and wonky hit boxes, and platforming aspects to the battle that are not great. You miss a jump, or an arm sends you flying into a pit, or both happen at once, and you're just left feeling increasingly agitated.
In Anor Londo, there are a pair of enemies that will snipe you if you're not careful. For a new player, it is a prohibitively difficult section of an otherwise interesting location, and being unable to figure out how to get past a specific enemy the right way will lead to yet another stupid death.
In DS2, the Old Iron King has a small arena surrounded by lava, there is one hole in the floor in a place the player will likely not see. It is often joked at how that hole is the true boss of the Iron Keep, because of how many players have either walked into it or have been knocked into it. An actual otherwise good implementation of instant death as a danger, but that one hole just does not have a reason to exist in the form that it does.
While the threat of instant death via environment can be an effective tool for tension, it is often overused, like jump scares, in horror games. Particularly RPG Horror games. In my experience, there are too often instances where it's more of an annoyance than something that drives fear. Being chased by a monster that will instantly kill you? Thrilling! Terrifying! Provided the level is designed well enough and escape is relatively easy.
Examining an item kills you, you restart, you examine another item, it also kills you, you restart... Not scary, annoying.
A monster will kill you instantly, or at least severely cripple you if you touch it without a defensive item? Terrifying, especially if there is a limited supply and few ways to actually kill the enemy. Actually pretty scary, because you know you can take a hit or two, so long as you have the requisite item. But without that item, it's just difficulty for difficulty's sake.
There was also another, extremely aggravating example in a horror RPG Maker game for Android. The game was free, but you had limited lives that recharged in real time, essentially, an energy system a la facebook game with associated microtransations. Glorious. The particular section I am referring to is where you have to race across a room, grab an item, and get the hell out of dodge before you died instantly. The timing was ****ing precise. And with only three lives and literal hours to wait for another one, it took me days to get past because I often died a single tile away from leaving the room. It was scary and tense at the beginning, and surreal as heck, but the more I died to this one, single area, the more I just got angry. I did manage to beat it, it was possible to beat, but boy howdy did it feel like an explicit way to try to get me to spend money on extra lives.
Yes, the threat of death is a useful tool for creating tension, if used properly and sparingly. the Doom status as seen in Final Fantasy, Petrify, being removed from battle, these are useful tools for generating tension in a battle. Doom literally counts you down how many turns you have to kill the enemy, and can also be good for resource management gameplay. Similar with Petrify, which you need to heal or your party could be effectively instantly killed. In FFX, being attacked again could remove that party member for the rest of battle. Getting blasted out of combat can also be useful, provided the player can counter it effectively and consistently.
Ultimately, it comes down to how you balance this threat of death with the player's ability to do something about it. Falling in a pit will kill you, so avoid them. This monster is chasing you, leave the area to escape it or die. This on-field enemy will kill you unless you have an item that stuns it (which you could even add a place to obtain more, yet limited amounts, of these items technically infinitely), you must solve this puzzle within X minutes or be crushed, you need to reach the end of a room, grab an item, and leave before a nursery rhyme finishes (Seriously, don't do this if you use microtransations + limited lives. Just don't.), there are so many ways you can use it, but you need to use it sparingly.
