Once every fifty years, the Maruhage Empire holds a tournament of all block leaders and management. Having to go through various battles and bizarre landscapes to collect enough tokens, the last one standing will become the next Maruhage Emperor.
The fifth tournament was unique both in the intervention of forces fighting against the empire (Bo-bobo and his team) as well as the invasion of Hydrate and the Reverse Maruhage Empire, disrupting the battles and forcing enemies to come together to stop him. However, it is possible that this playoff may have been used by Tsuru Tsurulina IV to eliminate all his enemies, allowing him to continue his leadership.
There are several ways for a participant to enter the tournament that is known:
- Be a current or former block leader or manager within the Maruhage Empire. (all Block Leaders and Former Block Leaders, including Tokoro Tennosuke and Dengakuman, are eligible for participation)
- Be an associate who comes along or knows of the tournament. (Softon and Hatenko enter via this route, as do certain notable minions or assistants like OVER's 5-Ninshu, the Three Prison-Murderer Brothers and Despair-kun)
- Defeat Bo-bobo and his allies (both Kuunyan and a mole attempt to enter this way; both failing to do so)
- Win a medal from another participant (due to Bo-bobo being ineligible under typical circumstances for being the enemy, he enters this way by defeating Nenchaku)
The tournament is a battle for survival, where the weak are weeded out and the strong make their way to the top. The participants must make their way through several difficult obstacles where all out battle awaits around every corner and with several stages of battle awaiting them:
- Upon initially entering the tournament battleground (through a special entrance in Egypt), all competition is sorted through into various preliminary groups where each must go through a certain preliminary of an unknown kind. Every preliminary route is protected by a guardian and only those who surpass the guardian can continue into the main tournament. You do not have to directly engage the guardian, merely pass them.
- Those who make it to the main gathering area are given a medal, these medals are based upon their strength and notability within the Maruhage Empire. It is possible for those to increase their standing but only by defeating one of a higher badge rank. The ranking as follows:
- Gold Lion Badge (for those identified by the empire as the strongest)
- Silver Pig-chan Badge (for those weaker than Gold Lion badge holders)
- Copper Nattou Badge (for those weaker than Silver Pig holders)
- Scrap Iron Poop Badge (a special badge made just for Tennosuke and Dengakuman in particular)
- Those with badges are allowed entry into Black Mountain, a massive structure with multiple paths leading up to Maruhage Castle. The mountain is split into several battlegrounds of varying styles and appearance. Once on the battlegrounds, the object becomes simply a matter of collecting 10 of any kind of badge while avoiding all others attempting to take your badge. As you collect the badges, you attempt to make your way up the mountain while surviving all those attempting to attack you likewise.
- Upon reaching Maruhage Castle with 10 badges in hand, you must present them to allow for entry into the castle appropriately. Anyone is allowed in as long as they have 10 badges (even if they didn't directly take part in the tournament and get the badges without effort)
- There is no further information as to what happens inside the castle to all those who make it that far: all participants who succeeded to get inside are subsequently defeated by Reverse Maruhage's Crimson and Love for use in summoning Hydrate to the surface. However, from his intentions prior to running off and abdicating, Tsurulina the IV was determined to fight to keep the throne at all costs by using his wife Mako-chan as his representative in battle, hinting they possibly would have faced her if it weren't for the Reverse Maruhage crisis.
 The badges are as followed: The Gold Lion Badge, The Silver Pig-san Badge, The Copper Nattou Badge.
- Bobobo-bo Bo-bobo
- Infinite Kicker
- The Three Civilizations
- Ujikin TOKIO
- Higusari Seijuro
- Dark Yasha
- Don Patch
- Tokoro Tennosuke
- The Teacup
- Super Rabbit
- Associate Hair Hunters #5 & #6
- Jeda the Wind God
- Jet K
- Wild Challenger
- Luigi Anna
- Silent Yamada
- Mick Nick
- ↑ http://mangahelpers.com/t/strangerataru/releases/2591 - Bo-bobo chapter 165