Playing in hard mode is a challenge in and of itself, and yet a lot of video games make you work for it by locking it behind a full completion.
In fact, some titles go even further and turn unlocking their hard modes into a full series of extreme challenges. From winning impossible fights to solving mysteries and going on scavenger hunts in the game's files, the only way to get to play on these secret hard modes is to go the extra mile and do something extraordinary and extraordinarily difficult.
You're likely never even going to know these hard modes exist until you discover the secret to unlocking them. It's almost as if the developers weren't content with letting you get your behind handed on higher difficulty settings and needed to find a way to punish you even more.
The fruits of hard labor have never tasted so bitter, as they do with the following secret hard modes. Your reward for taking on the challenge of unlocking them is being able to suffer some more.
10. Wes - Don't Starve
The survival game Don't Starve provides the player with a wide range of playable characters with special abilities and quirks.
Most of these characters are unlocked by gaining experience points, but some of them are locked behind special challenges that you must complete in the game. And to make things more interesting, one of these special secret characters is designed specifically to make survival more difficult.
Wes is a secret mime character that the player can unlock by rescuing him while completing Maxwell's challenge maps. He is considered a "hard mode" character by Don't Starve's community as he has the lowest stats of all the characters in the game and, being a mime, he is unable to speak, forcing you to identify objects and Wes's needs all by yourself.
The character is designed with veteran players in mind, providing them with a considerable challenge when they want to survive without any extra gimmicks and with barely enough health and sanity to feel comfortable.
Which is probably why you have to complete a series of challenges before you can even play as him.