Audience-Alienating Premise: The Ultimate Cliffhanger, as it proved to be impossible to beat for 2 tournaments, during a time when the ratings were severely decreasing to begin with. To elaborate, the obstacle was twice as long as the previous versions of the Cliffhanger, meaning that it took people a long time to get past it, if their strength didn't run out due to the previous 3 obstacles all being difficult stamina-drainers in their own right. It essentially removed the audience's desire to watch contestants run the course since it was extremely unlikely that anyone could get past it to the next stage, making each episode with it a Foregone Conclusion. Exacerbating this is that a number of episodes for these seasons would naturally end on this stage. It ultimately called for the entire 3rd Stage to be toned down in SASUKE 27 just to make sure people even cleared it, and even then, 5 out of the 8 people who got to the obstacle failed it. This is why the Crazy Cliffhanger was scaled down in length to just 4 ledges (One of which is incredibly small and only used to provide a grip for the transition to the last ledge), due to how the Ultimate Cliffhanger dominated the stage and prevented anyone from moving beyond it.
Common Knowledge: A prominent one with Kane Kosugi, who suddenly stopped competing after SASUKE 8; many fans assumed that this was due to a video game made by the SASUKE producers that used his likeness without permission, causing him to swear to never compete again...which might have held more water if not for the fact that Kane continued to compete in Pro Sportsman No. 1, a show made by the same company, for three more years after SASUKE 8. The truth of the matter seems to relate more to his career needs due to the rigors required to compete on a show like SASUKE in the first place; indeed, for his return in SASUKE 40, Kane needed to undergo a specialized training regiment to prepare.
The Shin-SASUKE Final Stage (18-24), due to Hype Backlash. Originally teased as a monstrously difficult Spider Climb-Triple Rope Climb combination after the Spider Climb-Rope Climb was finally defeated by Makoto Nagano, it became a topic of speculation due to the obstacles being unknown, as well as the overall increased difficulty in the course during this era. When it was revealed to merely be a Rope Ladder-Bungee Rope Climb combination with a much higher time limit than the previous Final Stage (45 seconds, which was lowered to 40 versus the previous one being 30 seconds), and only a 0.5 meter height increase, some may have considered it anti-climatic. It didn't help that it was beaten only three tournaments after it was first attempted, compared to how it took the previous Final Stage eleven tournaments after its first attempt.
The SASUKE 27 Final Stage was only 20 meters high, meaning it was actually shorter than its predecessor. It only consisted of a Rope Climb with a 40-second time limit. Considering that SASUKE 25 had introduced obstacles such as the Double Salmon Ladder and Ultimate Cliffhanger, one can't help but have expected something a bit more difficult. Said Final Stage was also defeated the first tournament it was attempted, eliminating Ryo Matachi, but being utterly destroyed by Yuuji Urushihara.
Ensemble Dark Horse: Minoru Kuramochi, a.k.a "Mr. Octopus." An elderly pub owner hailing from Edo, he entered the competition 19 times in total and usually never made it past the first obstacle, but the crowds and the fandom loved him for his spirit and cute octopi-related gimmick. He has been ranked at number 4 on G4's craziest contestant poll and the number 4 reason to worship Ninja Warrior.
Germans Love David Hasselhoff: It's a big hit in Australia, so much so that they have their own version titled Australian Ninja Warrior.
Harsher in Hindsight: Some people complained that the English announcer Stuart Hall sounded like a pedophile, which was noticeable in the Kunoichi commentary. In 2013, Hall plead guilty to several charges regarding sexual assaults against minors and more charges are coming his way. As a result, the British version removed his dub and redubbed it with Jim North's commentary. Doesn't help matters when this conviction reminds the British of the Jimmy Savile controversy.
It's the Same, Now It Sucks!: A common criticism that has appeared ever since Morimoto's first total victory concerning the course; many of the staple obstacles and format have remained the same; even the renewal in SASUKE 32 amounted to little more than three new obstacles (two of which were directly adapted from American Ninja Warrior so calling them "new" is a bit of a stretch) while the remaining changes were simply modifications to existing obstacles. The course has remained near completely static since then...which became most prominent in the renewal in SASUKE 39, which barely changed anything after Morimoto's second victory note The Silk Slider and Warped Wall were modified, and Stage 2 was completely unchanged. Only Stage 3 and the Final Stage received anything akin to a proper change. Granted, this particular case seems to be due to budget restraints, especially due to the COVID-19 Pandemic enforcing many restrictions on the course layout.
Scrappy Mechanic: There have been several duds on the course here and there.
Oftentimes, obstacles that are in place for just one tournament tend to fall into this category, due to being too easy or having a very poor concept/design.
The Backstream in Stage 2, which has remained on the course since SASUKE 28 isn't very popular with competitors or viewers due to it being a swimming obstacle, which is the opposite of the main goal of the course, which is not falling into the water. Heck, it's hated so much, it completely KILLED SASUKE 29's ratings due to controversy regarding the water jets used to make the obstacle harder (the severely reduced time limit from 135 seconds to 90 seconds didn't help either, as it resulted in only 6 out 17 people clearing the obstacle). Subsequent tournaments have not done it any favors, since the Nerf in SASUKE 30 just made it a glorified way to make the Wall Lift (and after SASUKE 32, the Reverse Conveyor) more difficult... while also resulting in a higher Stage 2 time limit, when the course is supposed to be a speed stage, even taking the Salmon Ladder into account. The fact that it has continued to stay, outlasting previous Stage 2 staples such as the Chain Reaction and Metal Spin, while being near-incapable of eliminating anyone by itself, continues to make it a glorified status-ailment obstacle.
The Swap Salmon Ladder. Many people considered it to be boring, as it consisted of nothing but ledge transitions and was only half of the height of the previous Salmon Ladders. In addition, mechanical problems with the obstacle, namely retracting rungs so people don't try to cheat their way up the obstacle, mean that the bottom two rung sets didn't retract, so if one end of the bar landed on them, it's an instant out. This problem became really apparent during SASUKE 30, prompting the Salmon Ladder Nobori/Kudari to be created for SASUKE 31.
The heat mechanic from KUNOICHI 8, where Stage 1 would be attempted by four competitors at the same time, and only the top two would be allowed to move on, even if all four completed the course. Multiple competitors who completed the first stage were eliminated because of being in a more competitive heat, including frontrunner and former finalist Waho Tanaka who was eliminated due to coming 3rd in her heat despite finishing the course within the time limit.
Similarly, the Repechage, or the "Second Chance" round also from KUNOICHI 8. In this round, members of a heat which had no one advance to Stage 2 would be able to compete again where one person from each heat would be able to advance to the next stage. Due to the combination of this only being available to competitors from less competitive heats and the aforementioned rule where a player would be eliminated if they finished in the bottom half of their heat even if they completed the course, meant that a total of nine competitors who failed Stage 1 advanced over competitors who completed Stage 1 by virtue of being in a less competitive heat. All nine competitors who advanced through the Repechage were eliminated in Stage 2 and the Repechage has never been used in any competitor before or since.
Shocking Elimination: Arguably every time an "All-Star" (save Katsumi Yamada) fails to make it past Stage 1, though this has become less of a shock as time went on due to both the courses getting harder and the "All-Star" competitors aging.
Omori Akira was one of the most dominant competitors in the early history of the show. In the first three tournaments, he reached the final stage each time and was only thwarted by the formidable Rope Climb. Not even the introduction of the dreaded Rolling Log in the third competition had been able to stop him from clearing the first stage with ease. Fast forward to the next tournament, and he failed that exact same Rolling Log note During the Rolling Log's debut, only two metal poles were used for the track; during Omori's run, the log simply slid down the tracks due to the bouncy design. SASUKE 4 implemented proper support structures onto the track so the log would actually roll.. Not only that, but he would never clear the first stage again despite his early success.
Three-time winner Ayako Miake in KUNOICHI 7 on Stage 2, failing the final obstacle, the Swinging Beams. It was the first time she ever failed the course.
In SASUKE 27, Li En Zhi failing the first obstacle of the first stage, after having made it past the first stage in the last 6 attempts.
Despite nearly winning the previous two competitions, Waho Tanaka was eliminated in the first stage of KUNOICHI 8 due to coming 3rd in her heat, despite completing the course in time.
For Stage 1, it tends to be the jumping obstacles (Jump Hang, Jumping Spider, Jump Hang Kai, Double Pendulum, and Dragon Glider. They all involve jumping off a trampoline onto another section (Nets for the Jump Hangs, the Spider Walk for the Jumping Spider, and a bar for the Double Pendulum and Dragon Glider, albeit with different functions regarding the two) of the course, and tend to have the highest failure rates on the course.
Another Stage 1 example is the classic Warped Wall. It's simply running up a 5.5 meter-high quarter-pipe, but the fact that it's been in the course since SASUKE 5 should give you a hint as to why it's still here (Even with variations like the Great Wall and Double Warped Wall, which didn't last long before reverting to the original version): it tends to be near the end of the stage, and as a result, most competitors get winded by the time they make it here, and while it cannot be failed except by time-outs, each additional attempt you make drains away your allotted time and remaining stamina, and has happened to many competitors over the years.
Stage 2's was the Spider Walk in early tournaments, due to how long it was versus the short 50-second time limit, but as the Stage evolved into a speed-stage, the time limit itself became the issue. After Nagano's victory however, the Salmon Ladder immediately proved itself as this, where you have to jump a bar onto an ascending set of rungs. It requires great upper body-strength, and is one of the first obstacles to deal with in the course. Even if competitors have figured out the proper technique and trained for this obstacle, it can still take away a good chunk of the time limit and like the Cliffhanger below, tends to receive modifications to make it harder.
Stage 3 has the Cliffhanger, where you have to move laterally while hanging on to a ledge about one knuckle deep, has ruined the runs of many competitors ever since it was introduced in SASUKE 4, with one version lasting from SASUKE 9 all the way to 17. The Shin-Cliffhanger seemed impossible until competitors started figuring out the proper swinging technique to get across the enlarged gap, the Ultimate Cliffhanger was so difficult the entire stage had to be nerfed just to make it possible, and the Crazy/Ultra-Crazy Cliffhangers' backwards swing technique is extremely difficult to time.
Another obstacle in Stage 3 is the Pipe Slider: Slide a bar to the end of the track, swing across a gap, and you're past the stage. The problem? It's the last obstacle, meaning competitors are extremely winded when they attempt it, and the bar tends to slide out of position when making the jump. Its introduction in SASUKE 2 wiped out most of the field, and after SASUKE 5, it became of the few non-Final Stage obstacles to have a zero percent clear-rate in some tournaments.
Some of the most tragic failures in the show's history (Yamada Katsumi in Sasuke 6 and 10, Yamamoto Shingo in Sasuke 5, Takeda Toshihiro multiple times, Akiyama Kazuhiko in Sasuke 12, Shiratori Bunpei in Sasuke 13 and 16 etc) have been caused by the Pipe Slider. The case of Takeda is particularly sad because he never managed to clear it in spite of all his efforts. This one obstacle single-handedly kept him from ever reaching the final stage and even caused him to badly injure his shoulder in the 12th tournament.
And of course, the Final Stage tower. Only a 30-45 second time limit to climb up whatever obstacles have been presented, each version having its own peculiarities. The Spider Climb/Rope Climb variations in particular, tend to be the hardest, as they have a strict time limit of 30 seconds versus a 22.5/24 meter climb, with the 22.5 variation having the Spider Climb walls separate after 15 seconds. Remember that only four people have ever beaten it (with Yuuji Urushihara doing it twice) in a 35+ tournament span.
The Woobie: Katsumi Yamada's legacy of failure and the consequences in his personal life.
Kazuhiko Akiyama as well. After his victory, his health worsened and his sight started to fade. The announcers always let us know about this fact.
