Obstacles that cause instant death have long been a staple in video games. They tend to be most common in platformer games, and usually old ones from the NES or SNES. They are as they sound - touch them, and the player dies instantly. In some cases, they can be used right and add tension for the player. More often than not though, instant death traps are placed in poor ways, explained poorly to the player, or just waste the player's time.
Mighty No. 9[]
Perhaps the most egregious case of instant death trap abuse in recent years is in Mighty No. 9. A throwback to old Mega Man games, this game perhaps goes too far in reminding the player how old platformers used to be.
Take these giant purple turbines in Mighty No. 3's stage. These are instant death if the player touches them, and are poorly designed from several perspectives.
Firstly, their hitboxes are unclear. How close can the player stand next to them before they die? Is the hitbox the purple color, or the actual turbine?
Second, the only way to pass this particular obstacle is to use a move that is not explained clearly to the player and serves little other purpose in the game. The player can dash low to the ground if they hold down and hit the dash button, but they never need to use this ability before this. It's hard to tell where they need to start the dash either, because they haven't needed to use their dash ability with precision before either.
Third, this is boring level design. The player is in no real danger here - there are no enemies around and no time challenge. They either dash under the obstacle, or they die instantly. If they get through it, the player won't feel challenged, and if they die, they feel cheated.