B4F was Tougher than B3F because B4F contained Fighters that were super fast and had good strength, both brothers fought 20 guards each which took them less than an hour, they said that the guards were strong but they lacked durability and endurance. But now at B5F Things had Taken a turn, there were only 4 Guards But all of them had the ability that the Guards on B4F lacked, While fighting 2 guards Satan Felt like He was fighting against Himself, hearing that from Satan Made it clear that they were no joke, Yami and Satan had To use each and every combo they had learnt and created, every ounce of their strength was required to defeat these beasts, But then, As soon as Yami Started getting weak, Satan Knocked all 4 of them out in one single strike, Yami asked him what was that, Satan replied with : "I don't know I saw karate low kick on their necks and as soon as I did one karate low kick they all were knocked out".