According to the spoilers for My Hero Academia chapter 405, the manga has set up the fight between Katsuki Bakugo and All For One. Given that Bakugo is the series' deuteragonist and All For One is the secondary villain, fans love the fact that the two characters are set to face each other in the final battle.
However, from the information provided by My Hero Academia chapter 405 spoilers, it seems glaringly obvious that Bakugo is going to lose against All For One. When one compares the two characters and their injuries, it does seem like they are at an equal level. Unfortunately, in reality, the battle isn't as evenly matched as fans wish it would be.
Disclaimer: This article contains spoilers from the My Hero Academia chapter 405.
My Hero Academia chapter 405 may have set up Bakugo for his biggest defeat
For fans who may have forgotten, Tomura Shigaraki had punctured Bakugo's heart, forcing him to draw his possible last breaths. That's when Edgeshot came to his rescue and entered him, hoping to help fix his internal injuries.
Fortunately, as revealed in My Hero Academia chapter 405 spoilers, Edgeshot managed to mend Bakugo's bones and organs. However, as warned by the hero himself, Bakugo's body wasn't in an ideal condition to fight. For that reason, he was set to constantly feel excruciating pain all over his body.
Considering Edgeshot's warning, it seemed pretty evident that the treatment he provided to the young hero was essentially to keep him alive. It was just a temporary stopgap meant to prevent his death so that he could be healed later, which would only happen if Bakugo gave his body some rest and allowed it to recover.
Nevertheless, upon waking up from his long slumber, Katsuki Bakugo re-entered the battlefield to save his idol, All Might. While one could understand his emotions for wanting to rescue All Might, there is no reason for him to keep fighting and go up against All For One in his condition. Therefore, his defeat seems pretty much evident.
One should note that Bakugo's Quirk also puts a lot of force on him due to the blasts required to levitate him and attack the opponent. Such jerks are bound to damage his internal injuries further. Thus, Bakugo poses a threat to himself as his Quirk could essentially increase the pain that he was already set to face due to his injuries.
If all such factors are calculated, the only logical method of winning for Bakugo seems to be a support item.
According to My Hero Academia chapter 405 spoilers, All Might gives Bakugo a gauntlet that he named after the young student's hero name. From the premise, it seems like the gauntlet is quite powerful. Hence, if Bakugo fails to efficiently use the support item, his defeat is essentially guaranteed.
Additionally, one must not forget that All For One is a crafty villain. Despite the odds stacked against him, he should be able to concoct a devious plan that may see him defeat the series' deuteragonist easily.