chase sequence

A situation in a form of Media (Such as Videogame or Movie) where a Character is fleeing from something in pursuit of said character, usually in an attempt to kill them. Usually, attempting to attack the Pursuer in normal ways is futile, and the only way to survive is to escape.
Perhaps a good example would be in the Waterfall area of Undertale, where Undyne appears in a couple of areas to attempt to kill you via stabbing you with magic Spears, and the only way out is to escape her.
More good examples reside in the Resident Evil series, but I won't go into them because Spoilers.

Person: "I swear, this chase sequence is so hard!"
Other Person: "Who, or what were you running from?"
Person: "a fucking plane engine with legs."