@izzythepush,
There are so many challenges out there that are both ridiculous and dangerous.
For instance:
Eyeballing - Where you place a bottle of alcohol (vodka, usually) directly against your eyeball. Supposedly it allows you to get a buzz faster. Result: Possible harm to the eye.
Cinnamon challenge: Eat a spoon of cinnamon. IT immediately absorbs all the moisture in the mouth. It leads to irritated airways, coughing and possible lng damage (up to and including collapsed lungs).
Planking: Just laying rigid(like a plank, hence the name). It's not inherently dangerous, but over time, this one has gone to extremes: reportedly, an Australian kid I believe died because he fell from a balcony on the seventh floor he was planking on.
Car Surfing: Well, does this need an explanation? It gets even worse when the driver does it...
Hot water challenge: Either drink boiling hot water or pour it over your body.
Eraser challenge: Vigorously rubbing an eraser over your skin while fulfilling a mundane task (such as reciting the alphabet). Results in permanent scars...
Fire challenge. This one takes the cake. It involved pouring a flammable liquid on your skin, and then setting yourself on fire...
There are others, this is just a sample. It's completely ludicrous...