Watching people fall unexpectedly is our guilty little pleasure, so what could possibly make it better? How about Japan’s legendary assassins popping in at opportune moments to cause such falls? Face plants are great, but when they're caused by a ninja they become a lot funnier. Don’t take our word for it though—see the video above.

Ninja are Japan’s master spies and their exploits are legendary and mythical. They carefully sneak through the darkness, attack, and then retreat like they were never there in the first place. When they attack, it is usually with deadly consequences, which is why it’s so amusing to see them “cause” human clumsiness.

YouTube channel FailArmy normally compiles fail videos from around the internet, but in this video where they add their own Fail Ninja, the laughs rise to comedy gold. It’s hard to tell when or where the Fail Ninja will strike, but his attacks are vicious and hysterical.

It’s hilarious to imagine the ninja toying with their adversaries, the samurai, in this way, but from history, we know that their rivalry is much, much more serious. Although, we all know history’s greatest battle is Pirates vs. Ninjas!

Related Stories:
Which anime fighting techniques would win in real life? Fans give their answer with comedic video
Add a bit of adventure to your tour of Asakusa with a ninja experience!!
Japanese dog accidentally reveals his secret superpower! Oops, now it’s on the Internet